Inventory sequence

From Rosetta Code
Inventory sequence is a draft programming task. It is not yet considered ready to be promoted as a complete task, for reasons that should be found in its talk page.

To build the inventory sequence, first take inventory of what numbers are already in the sequence, then, starting with 0 add the count of each number in turn to the end of the sequence. When you reach a number that has a count of 0, stop, add the 0 to the end of the sequence, and then restart the inventory from 0.


E.G.
Start taking inventory; how many 0s are there? 0. Add a 0 to the end of the sequence and restart the inventory. (0)
How many 0s are there? 1. Add a 1 to the end of the sequence. How many 1s are there? 1. Add a 1 to the end of the sequence. How many 2s are there? 0. Add a 0 to the end of the sequence and restart the inventory. (0 1 1 0)
and so on.


Task
  • Find and display the first 100 elements of the sequence.
  • Find and display the position and value of the first element greater than or equal to 1000.


Stretch
  • Find and display the position and value of the first element greater than or equal to 2000, 3000 ... 10,000.
  • Plot a graph of the first 10,000 elements of the sequence.


See also


ALGOL 68

Calculates the sequence elements without storing them.

BEGIN # find elements of the inventory sequence                                #

    INT next to show :=  1 000;           # next value to show first element > #
    INT max to show   = 10 000;           # last value to show first element > #

    INT max number    = max to show + 1 000;  # max. element value to consider #
    [ 0 : max number ]INT occurs;         # number of times each number occurs #
    FOR i FROM LWB occurs TO UPB occurs DO occurs[ i ] := 0 OD;
    INT seq pos      := 0;                       # current end of the sequence #
    WHILE next to show <= max to show DO
        FOR n FROM 0 WHILE next to show <= max to show
                       AND BEGIN
                               INT element := occurs[ n ];
                               seq pos    +:= 1;
                               IF seq pos <= 100 THEN
                                   print( ( " ", whole( element, -4 ) ) );
                                   IF seq pos MOD 10 = 0 THEN print( ( newline ) ) FI
                               ELIF element > next to show THEN
                                   print( ( "Element ", whole( seq pos, -8 )
                                          , " (", whole( element, -8 )
                                          , ") is first > ", whole( next to show, -6 )
                                          , newline
                                          )
                                        );
                                   next to show +:= 1 000
                               FI;
                               IF element < max number THEN
                                   occurs[ element ] +:= 1
                               FI;
                               element /= 0
                           END
        DO SKIP OD
    OD

END
Output:
    0    1    1    0    2    2    2    0    3    2
    4    1    1    0    4    4    4    1    4    0
    5    5    4    1    6    2    1    0    6    7
    5    1    6    3    3    1    0    7    9    5
    3    6    4    4    2    0    8    9    6    4
    9    4    5    2    1    3    0    9   10    7
    5   10    6    6    3    1    4    2    0   10
   11    8    6   11    6    9    3    2    5    3
    2    0   11   11   10    8   11    7    9    4
    3    6    4    5    0   12   11   10    9   13
Element    24256 (    1001) is first >   1000
Element    43302 (    2009) is first >   2000
Element    61709 (    3001) is first >   3000
Element    81457 (    4003) is first >   4000
Element    98705 (    5021) is first >   5000
Element   121343 (    6009) is first >   6000
Element   151757 (    7035) is first >   7000
Element   168805 (    8036) is first >   8000
Element   184429 (    9014) is first >   9000
Element   201789 (   10007) is first >  10000

FreeBASIC

Dim As Integer max = 10000
Dim As Integer inv()
Dim As Integer counts(max + 100)
counts(0) = 1
Dim As Integer lower = 100
Dim As Integer upper = 1000
Dim As Boolean done = False
Dim As Integer ix = 0
While Not done
    Dim As Integer i = 0, c = 0
    Do
        Dim As Integer j = counts(i)
        If Ubound(inv) < max Then 
            Redim Preserve inv(ix+1)
            inv(ix+1) = j
        End If
        counts(j) += 1
        ix += 1
        If Ubound(inv) >= lower Then
            Print "Inventory sequence, first 100 elements:"
            For c = 0 To 99
                Print Using "###"; inv(c);
                If (c+1) Mod 20 = 0 Then Print
            Next 
            lower = max + 1
        End If
        If j = 0 Then Exit Do
        If j >= upper Then
            Print Using !"\nFirst element >= ##,### is ##,### at index ###,###"; upper; j; ix;
            If j >= max Then done = True: Exit Do
            upper += 1000
        End If
        i += 1
    Loop
Wend

Sleep

J

   nextinv=:  ((*@] * 1+{.@[), }.@[ , ]) +/@({. = }.)

   10 10$}.nextinv^:100]0   NB. first 100 elements of inventory sequence
 0  1  1  0  2  2  2  0  3  2
 4  1  1  0  4  4  4  1  4  0
 5  5  4  1  6  2  1  0  6  7
 5  1  6  3  3  1  0  7  9  5
 3  6  4  4  2  0  8  9  6  4
 9  4  5  2  1  3  0  9 10  7
 5 10  6  6  3  1  4  2  0 10
11  8  6 11  6  9  3  2  5  3
 2  0 11 11 10  8 11  7  9  4
 3  6  4  5  0 12 11 10  9 13
   ({:,_2+#)nextinv^:(1000>{:)^:_]0   NB. first value of at least 1000 and its index
1001 24255

The inventory sequence has a "hidden value" which is the number that we are searching for, and counting. So, here, we include it as the first element of the representation of an inventory subsequence. And nextinv calculates both the next "hidden value" as well as the corresponding subsequence which incorporates a count of how many times the current "hidden value" appeared.

For the task, we iterate inductively from the initial state (either a 100 times or until we find a value which is greater than 1000).

It would be more efficient to maintain counts of each integer so far encountered, but that efficiency is not necessary for this task (and would require more code).

That said, here's a faster implementation:

invseq=: {{
  cnt=. 0, seq=. i. nxt=. 0
  while. -. u seq do.
    k=. nxt{cnt
    nxt=. (*k)*nxt+1
    cnt=. (1+k{cnt) k} cnt=. cnt {.~ (2+k)>.#cnt
    seq=. seq, k
  end.
}}
   stretch=: }.nextinv^:(10000>{:)^:_]0    NB. or
   stretch=: (1e4<:{:) invseq   NB. equivalent, faster approach

   (,~ {&stretch) {.I.2000<stretch   NB. first value greater than 2000 and its index
2009 43301
   (,~ {&stretch) {.I.3000<stretch
3001 61708
   (,~ {&stretch) {.I.4000<stretch
4003 81456
   (,~ {&stretch) {.I.5000<stretch
5021 98704
   (,~ {&stretch) {.I.6000<stretch
6009 121342
   (,~ {&stretch) {.I.7000<stretch
7035 151756
   (,~ {&stretch) {.I.8000<stretch
8036 168804
   (,~ {&stretch) {.I.9000<stretch
9014 184428
   (,~ {&stretch) {.I.10000<stretch
10007 201788
   require'plot'
   plot 1e4{.stretch

jq

Works with both jq and gojq, the C and Go implementations of jq

... but note that gojq takes about 5 times longer (and requires much more memory) to complete the task.

With minor modifications, the program below also works quite snappily with jaq, the Rust implementation of jq.

The definition of `_nwise` can be omitted if using the C implementation of jq.

def _nwise($n):
  def n: if length <= $n then . else .[0:$n] , (.[$n:] | n) end;
  n;

# Emit the inventory sequence ad infinitum
def inventory_sequence:
  {num: 0,
   emit: 0,
   inventory: {} }
   | foreach range(0; infinite) as $n (.;
       .emit = (.inventory[.num|tostring] // 0) 
       | if .emit == 0 then .num = 0 else .num += 1 end
       | .inventory[.emit|tostring] += 1 )
   | .emit ;

# Report on the progress of an arbitrary sequence, indefinitely
# Emit [.next, $x, .n]
def probe(s; $gap):
  foreach s as $x ({n: 0, next: $gap};
    .n += 1
    | if $x >= .next then .emit = {next, $x, n} | .next += $gap
      else .emit = null
      end)
  | select(.emit).emit;

def lpad($len): tostring | ($len - length) as $l | (" " * $l)[:$l] + .;

def task($n):
  [limit($n; inventory_sequence)] | _nwise(10) | map(lpad(3)) | join(" ");

task(100),
"",
(limit(10; probe(inventory_sequence; 1000))
 | "First element >= \(.next) is \(.x) at index \(.n - 1)")
Output:
  0   1   1   0   2   2   2   0   3   2
  4   1   1   0   4   4   4   1   4   0
  5   5   4   1   6   2   1   0   6   7
  5   1   6   3   3   1   0   7   9   5
  3   6   4   4   2   0   8   9   6   4
  9   4   5   2   1   3   0   9  10   7
  5  10   6   6   3   1   4   2   0  10
 11   8   6  11   6   9   3   2   5   3
  2   0  11  11  10   8  11   7   9   4
  3   6   4   5   0  12  11  10   9  13

First element >= 1000 is 1001 at index 24255
First element >= 2000 is 2009 at index 43301
First element >= 3000 is 3001 at index 61708
First element >= 4000 is 4003 at index 81456
First element >= 5000 is 5021 at index 98704
First element >= 6000 is 6009 at index 121342
First element >= 7000 is 7035 at index 151756
First element >= 8000 is 8036 at index 168804
First element >= 9000 is 9014 at index 184428
First element >= 10000 is 10007 at index 201788

Julia

""" rosettacode.org/wiki/Inventory_sequence """

using Printf
using Counters
using Plots

struct InventorySequence
    inventory::Counter{Int}
    InventorySequence() = new(counter([0]))
end

function Base.iterate(i::InventorySequence, num = 0)
    nextval = i.inventory[num]
    num = nextval == 0 ? 0 : num + 1
    i.inventory[nextval] += 1
    return nextval, num
end
    
const thresholds = [1000 * j for j in 1:10]
const toplot = Int[]

for (i, n) in enumerate(InventorySequence())
    if i <= 100
        print(rpad(n, 4), i % 20 == 0 ? "\n" : "")
    elseif n >= thresholds[begin]
        @printf("First element >= %d5: %d5 in position %d.\n", popfirst!(thresholds), n, i)
        length(thresholds) == 0 && break
    end
    length(toplot) < 10000 && push!(toplot, n)
end

plot(toplot)
Output:

Similar to Python output.

Mathematica/Wolfram Language

(*Function to generate the inventory sequence*)
InventorySequence[terms_] := 
 Module[{num = 0, alst = {0}, inventory, c}, inventory = <|0 -> 1|>;
  Table[c = Lookup[inventory, num, 0];
   num = If[c == 0, 0, num + 1];
   alst = Append[alst, c];
   inventory[c] = Lookup[inventory, c, 0] + 1;, {n, 2, terms}];
  alst]

(*Generate the inventory sequence*)
biglist = InventorySequence[201790];

(*Print first 100 elements of the sequence*)
partitioned = Partition[Take[biglist, 100], 10];
Do[Print[Row[partitioned[[i]], " "]], {i, Length[partitioned]}]


(*Find and print the first occurrences of elements>=thresholds*)
thresholds = 1000 Range[1, 10];
firstOccurrences = 
  Reap[Do[If[biglist[[i]] >= thresholds[[1]], 
      Sow[{thresholds[[1]], biglist[[i]], i}];
      thresholds = Rest[thresholds];
      If[Length[thresholds] == 0, Break[]];], {i, Length[biglist]}]][[
   2, 1]];

(*Print the formatted results*)
Do[Print["First element \[GreaterEqual] ", firstOccurrence[[1]], 
  " is ", firstOccurrence[[2]], " at index ", 
  firstOccurrence[[3]]], {firstOccurrence, firstOccurrences}]

(*Plot the first 10,000 elements of the sequence*)
ListPlot[biglist[[1 ;; 10000]], Joined -> True, 
 PlotStyle -> {Thin, Blue}, PlotRange -> Full]
Output:
  0   1   1   0   2   2   2   0   3   2
  4   1   1   0   4   4   4   1   4   0
  5   5   4   1   6   2   1   0   6   7
  5   1   6   3   3   1   0   7   9   5
  3   6   4   4   2   0   8   9   6   4
  9   4   5   2   1   3   0   9  10   7
  5  10   6   6   3   1   4   2   0  10
 11   8   6  11   6   9   3   2   5   3
  2   0  11  11  10   8  11   7   9   4
  3   6   4   5   0  12  11  10   9  13
First element >= 1000 is 1001 at index 24256
First element >= 2000 is 2009 at index 43302
First element >= 3000 is 3001 at index 61709
First element >= 4000 is 4003 at index 81457
First element >= 5000 is 5021 at index 98705
First element >= 6000 is 6009 at index 121343
First element >= 7000 is 7035 at index 151757
First element >= 8000 is 8036 at index 168805
First element >= 9000 is 9014 at index 184429
First element >= 10000 is 10007 at index 201789
File:Plot the first 10, 000 elements of the inventory sequence.svg


Nim

import std/[strformat, tables]
import gnuplot

iterator inventorySequence(): (int, int) =
  var counts: CountTable[int]
  var idx = -1
  while true:
    var i = 0
    while true:
      let n = counts[i]
      inc idx
      counts.inc(n)
      yield (idx, n)
      if n == 0: break
      inc i

echo "First 100 elements:"
var x, y: seq[int]
var lim = 1000
for idx, n in inventorySequence():
  if idx < 10000:
    x.add idx
    y.add n
  if idx <= 100:
    stdout.write &"{n:>2}"
    stdout.write if idx mod 10 == 0: '\n' else: ' '
    if idx == 100: echo()
  elif n >= lim:
    echo &"First element ⩾ {lim:>5} is {n:>5} at index {idx:>6}"
    lim += 1000
    if lim > 10000: break

withGnuPlot:
  plot(x, y, "Inventory sequence", "with impulses lw 0.5")
  png("inventory_sequence.png")
Output:
First 100 elements:
 0
 1  1  0  2  2  2  0  3  2  4
 1  1  0  4  4  4  1  4  0  5
 5  4  1  6  2  1  0  6  7  5
 1  6  3  3  1  0  7  9  5  3
 6  4  4  2  0  8  9  6  4  9
 4  5  2  1  3  0  9 10  7  5
10  6  6  3  1  4  2  0 10 11
 8  6 11  6  9  3  2  5  3  2
 0 11 11 10  8 11  7  9  4  3
 6  4  5  0 12 11 10  9 13  8

First element ⩾  1000 is  1001 at index  24255
First element ⩾  2000 is  2009 at index  43301
First element ⩾  3000 is  3001 at index  61708
First element ⩾  4000 is  4003 at index  81456
First element ⩾  5000 is  5021 at index  98704
First element ⩾  6000 is  6009 at index 121342
First element ⩾  7000 is  7035 at index 151756
First element ⩾  8000 is  8036 at index 168804
First element ⩾  9000 is  9014 at index 184428
First element ⩾ 10000 is 10007 at index 201788

Perl

Library: ntheory
Translation of: Raku
use strict;
use warnings;
use feature 'say';

use List::AllUtils <max firstidx>;
use GD::Graph::bars;

sub comma { reverse ((reverse shift) =~ s/.{3}\K/,/gr) =~ s/^,//r }
sub table { my $t = 20 * (my $c = 1 + length max @_); ( sprintf( ('%'.$c.'d')x@_, @_) ) =~ s/.{1,$t}\K/\n/gr }

my($i, @inventory, %i) = 0;
do {
    my $count = $i{$i} // 0;
    $i = $count ? $i+1 : 0;
    ++$i{$count};
    push @inventory, $count
} until $inventory[-1] > 10_000;

say "Inventory sequence, first 100 elements:\n" .  table @inventory[0..99]; say '';

for my $n (map { $_ * 1000 } 1..10) {
    my $i = firstidx { $_ >= $n } @inventory;
    printf "First element >= %6s is %6s in position: %s\n", comma($n), comma($inventory[$i]), comma $i;
}

# graph
my @data = ( [0..5000], [@inventory[0..5000]] );
my $graph = GD::Graph::bars->new(800, 600);
$graph->set(
    title          => 'Inventory sequence',
    y_max_value    => 250,
    x_tick_number  => 5,
    r_margin       => 10,
    dclrs          => [ 'blue' ],
) or die $graph->error;
my $gd = $graph->plot(\@data) or die $graph->error;

open my $fh, '>', 'Perl-inventory-sequence.png';
binmode $fh;
print $fh $gd->png();
close $fh;
Output:
Inventory sequence, first 100 elements:
  0  1  1  0  2  2  2  0  3  2  4  1  1  0  4  4  4  1  4  0
  5  5  4  1  6  2  1  0  6  7  5  1  6  3  3  1  0  7  9  5
  3  6  4  4  2  0  8  9  6  4  9  4  5  2  1  3  0  9 10  7
  5 10  6  6  3  1  4  2  0 10 11  8  6 11  6  9  3  2  5  3
  2  0 11 11 10  8 11  7  9  4  3  6  4  5  0 12 11 10  9 13

First element >=  1,000 is  1,001 in position: 24,255
First element >=  2,000 is  2,009 in position: 43,301
First element >=  3,000 is  3,001 in position: 61,708
First element >=  4,000 is  4,003 in position: 81,456
First element >=  5,000 is  5,021 in position: 98,704
First element >=  6,000 is  6,009 in position: 121,342
First element >=  7,000 is  7,035 in position: 151,756
First element >=  8,000 is  8,036 in position: 168,804
First element >=  9,000 is  9,014 in position: 184,428
First element >= 10,000 is 10,007 in position: 201,788

Phix

-- demo\rosetta\Inventory_sequence.exw
with javascript_semantics
function inventory(integer limit)
    sequence inv = {0}, counts = {1}
    integer ix = 0, thousands = 1000
    while true do
        integer i = 0
        while true do
            integer j = iff(i>=length(counts)?0:counts[i+1])
            inv &= j
            while j>=length(counts) do counts &= 0 end while
            counts[j+1] += 1
            ix += 1
            if length(inv)=100 then
                printf(1,"Inventory sequence, first 100 elements:\n%s\n",
                         {join_by(inv,1,20,"",fmt:="%3d")})
            end if
            if j=0 then exit end if
            if j>=thousands then
                printf(1,"First element >= %,6d is %,6d at index %,7d\n", {thousands, j, ix})
                if j>=limit then return inv[1..limit] end if
                thousands += 1000
            end if
            i += 1
        end while
    end while
end function
constant lim = 1e4
sequence x = tagset(lim),
         y = inventory(lim)

include pGUI.e
include IupGraph.e
function get_data(Ihandle graph)
    integer {w,h} = IupGetIntInt(graph,"SIZE")
    IupSetInt(graph,"XTICK",iff(w<500?iff(w<350?iff(w<250?5000:2500):2000):1000))
    IupSetInt(graph,"YTICK",iff(h<350?iff(h<200?iff(h<150? 200: 100):  80):  40))
    return {{x,y,CD_BLUE}}
end function

IupOpen()
Ihandle graph = IupGraph(get_data,"XMIN=0,XMAX=10000,YMIN=0,YMAX=400"),
    dlg = IupDialog(graph,`TITLE=gGraph,SIZE=320x240,MINSIZE=240x140`)
IupShow(dlg)
if platform()!=JS then
    IupMainLoop()
end if
Output:
Inventory sequence, first 100 elements:
  0  1  1  0  2  2  2  0  3  2  4  1  1  0  4  4  4  1  4  0
  5  5  4  1  6  2  1  0  6  7  5  1  6  3  3  1  0  7  9  5
  3  6  4  4  2  0  8  9  6  4  9  4  5  2  1  3  0  9 10  7
  5 10  6  6  3  1  4  2  0 10 11  8  6 11  6  9  3  2  5  3
  2  0 11 11 10  8 11  7  9  4  3  6  4  5  0 12 11 10  9 13

First element >=  1,000 is  1,001 at index  24,255
First element >=  2,000 is  2,009 at index  43,301
First element >=  3,000 is  3,001 at index  61,708
First element >=  4,000 is  4,003 at index  81,456
First element >=  5,000 is  5,021 at index  98,704
First element >=  6,000 is  6,009 at index 121,342
First element >=  7,000 is  7,035 at index 151,756
First element >=  8,000 is  8,036 at index 168,804
First element >=  9,000 is  9,014 at index 184,428
First element >= 10,000 is 10,007 at index 201,788

Python

''' rosettacode.org/wiki/Inventory_sequence '''
from collections import Counter
from matplotlib.pyplot import plot

def inventory_sequence(terms):
    ''' From the code by Branicky at oeis.org/A342585 '''
    num, alst, inventory = 0, [0], Counter([0])
    for n in range(2, terms+1):
        c = inventory[num]
        num = 0 if c == 0 else num + 1
        alst.append(c)
        inventory.update([c])
    return alst

biglist = inventory_sequence(201_790)
thresholds = [1000 * j for j in range(1, 11)]

for i, k in enumerate(biglist):
    if i < 100:
        print(f'{k:<4}', end='\n' if (i + 1) % 20 == 0 else '')
    elif k >= thresholds[0]:
        print(f'\nFirst element >= {thresholds.pop(0):5}: {k:5} in position {i:6}')
        if len(thresholds) == 0:
               break

plot(biglist[:10_000], linewidth=0.3)
plt.show()
Output:
0   1   1   0   2   2   2   0   3   2   4   1   1   0   4   4   4   1   4   0   
5   5   4   1   6   2   1   0   6   7   5   1   6   3   3   1   0   7   9   5   
3   6   4   4   2   0   8   9   6   4   9   4   5   2   1   3   0   9   10  7   
5   10  6   6   3   1   4   2   0   10  11  8   6   11  6   9   3   2   5   3   
2   0   11  11  10  8   11  7   9   4   3   6   4   5   0   12  11  10  9   13  

First element >=  1000:  1001 in position  24255

First element >=  2000:  2009 in position  43301

First element >=  3000:  3001 in position  61708

First element >=  4000:  4003 in position  81456

First element >=  5000:  5021 in position  98704

First element >=  6000:  6009 in position 121342

First element >=  7000:  7035 in position 151756

First element >=  8000:  8036 in position 168804

First element >=  9000:  9014 in position 184428

First element >= 10000: 10007 in position 201788

Raku

use Lingua::EN::Numbers;

my ($i, %i) = 0;

my @inventory = (^∞).map: {
    my $count = %i{$i} // 0;
    $i = $count ?? $i+1 !! 0;
    ++%i{$count};
    $count
}

say "Inventory sequence, first 100 elements:\n" ~
  @inventory[^100].batch(20)».fmt("%2d").join: "\n";

say '';

for (1..10).map: * × 1000 {
    my $k = @inventory.first: * >= $_, :k;
    printf "First element >= %6s is %6s in position: %s\n",
      .&comma, @inventory[$k].&comma, comma $k;
}


use SVG;
use SVG::Plot;

my @x = ^10000;

'Inventory-raku.svg'.IO.spurt:
 SVG.serialize: SVG::Plot.new(
    background  => 'white',
    width       => 1000,
    height      => 600,
    plot-width  => 950,
    plot-height => 550,
    x           => @x,
    values      => [@inventory[@x],],
    title       => "Inventory Sequence - First {+@x} values (zero indexed)",
).plot: :lines;
Output:
Inventory sequence, first 100 elements:
 0  1  1  0  2  2  2  0  3  2  4  1  1  0  4  4  4  1  4  0
 5  5  4  1  6  2  1  0  6  7  5  1  6  3  3  1  0  7  9  5
 3  6  4  4  2  0  8  9  6  4  9  4  5  2  1  3  0  9 10  7
 5 10  6  6  3  1  4  2  0 10 11  8  6 11  6  9  3  2  5  3
 2  0 11 11 10  8 11  7  9  4  3  6  4  5  0 12 11 10  9 13

First element >=  1,000 is  1,001 in position: 24,255
First element >=  2,000 is  2,009 in position: 43,301
First element >=  3,000 is  3,001 in position: 61,708
First element >=  4,000 is  4,003 in position: 81,456
First element >=  5,000 is  5,021 in position: 98,704
First element >=  6,000 is  6,009 in position: 121,342
First element >=  7,000 is  7,035 in position: 151,756
First element >=  8,000 is  8,036 in position: 168,804
First element >=  9,000 is  9,014 in position: 184,428
First element >= 10,000 is 10,007 in position: 201,788

converted to a .png to reduce size for display here:


RPL

For efficiency reasons, two different programs are needed to generate the sequence or search for the first high value.

« → max   
  « { 0 1 1 0 }                              @ need to start with a non-null cycle to have ∑LIST work
     WHILE DUP SIZE max < REPEAT
        0 max FOR j 
           DUP 1 « j == » DOLIST ∑LIST       @ count occurrences in the list
           IF DUP NOT THEN max 'j' STO END
           +
        NEXT
     END 
     1 max SUB
» 'INVT' STO                                 @ ( n → { a(1)..a(n)} )

« DUP 1 + { } + 0 CON -1 → max counts j
  « 2 CF 1
    DO 'counts' 'j' INCR 1 +
       IFERR GET THEN DROP2 0 END
       IF DUP NOT THEN -1 'j' STO END
       IF DUP max > THEN 
          "element" →TAG SWAP "position" →TAG 2 SF
       ELSE 
          'counts' SWAP 1 + DUP2 GET 1 + PUT 1 +
       END
    UNTIL 2 FS? END
» » 'INVT1ST' STO                           @ ( n → 1st_value_>_n pos )
100 INVT
1000 INVT1ST
Output:
3: { 0 1 1 0 2 2 2 0 3 2 4 1 1 0 4 4 4 1 4 0 5 5 4 1 6 2 1 0 6 7 5 1 6 3 3 1 0 7 9 5 3 6 4 4 2 0 8 9 6 4 9 4 5 2 1 3 0 9 10 7 5 10 6 6 3 1 4 2 0 10 11 8 6 11 6 9 3 2 5 3 2 0 11 11 10 8 11 7 9 4 3 6 4 5 0 12 11 10 9 13 }
2: element: 1001
1: position: 24256

Ruby

Not actually counting but keeping count in a hash:

n = 0
counter = Hash.new(0)
inventory = loop.lazy.map do 
    c = counter[n]
    counter[c] += 1
    c == 0 ? n = 0 : n += 1
    c
 end
 inventory.first(100).each_slice(10){|s| puts "%4d"*s.size % s}
 puts

 (1000..10000).step(1000).each do |t|
   counter.clear
   puts "First element >= #{t} : %d index %d" % inventory.with_index.detect{|e,i| e > t}
 end
Output:
   0   1   1   0   2   2   2   0   3   2
   4   1   1   0   4   4   4   1   4   0
   5   5   4   1   6   2   1   0   6   7
   5   1   6   3   3   1   0   7   9   5
   3   6   4   4   2   0   8   9   6   4
   9   4   5   2   1   3   0   9  10   7
   5  10   6   6   3   1   4   2   0  10
  11   8   6  11   6   9   3   2   5   3
   2   0  11  11  10   8  11   7   9   4
   3   6   4   5   0  12  11  10   9  13

First element >= 1000 : 1001 index 24255
First element >= 2000 : 2009 index 43301
First element >= 3000 : 3001 index 61708
First element >= 4000 : 4003 index 81456
First element >= 5000 : 5021 index 98704
First element >= 6000 : 6009 index 121342
First element >= 7000 : 7035 index 151756
First element >= 8000 : 8036 index 168804
First element >= 9000 : 9014 index 184428
First element >= 10000 : 10007 index 201788

Wren

Library: DOME
Library: Wren-plot
Library: Wren-iterate
Library: Wren-fmt
import "dome" for Window
import "graphics" for Canvas, Color
import "./plot" for Axes
import "./iterate" for Stepped
import "./fmt" for Fmt

var max = 10000
var inv = [0]
var counts = List.filled(max + 100, 0) // say
counts[0] = 1
var lower = 100
var upper = 1000
var done = false
var ix = 0
while (!done) {
    var i = 0
    while(true) {
        var j = counts[i]
        if (inv.count < max) inv.add(j)
        counts[j] = counts[j] + 1
        ix = ix + 1
        if (inv.count >= lower) {
            System.print("Inventory sequence, first 100 elements:")
            Fmt.tprint("$2d", inv[0..99], 20)
            System.print()
            lower = max + 1
        }
        if (j == 0) break
        if (j >= upper) {
            Fmt.print("First element >= $,6d is $,6d at index $,7d", upper, j, ix)
            if (j >= max) {
                done = true
                break
            }
            upper = upper + 1000
        }
        i = i + 1
    }
}

// generate points for the plot
var Pts = (0...max).map { |i| [i, inv[i]] }.toList

class Main {
    construct new() {
        Window.title = "Inventory sequence - first 10,000 elements."
        Canvas.resize(1000, 600)
        Window.resize(1000, 600)
        Canvas.cls(Color.white)
        var axes = Axes.new(100, 500, 800, 400, 0..10000, 0..450)
        axes.draw(Color.black, 2)
        var xMarks = Stepped.new(0..10000, 500)
        var yMarks = Stepped.new(0..400, 50)
        axes.mark(xMarks, yMarks, Color.black, 2)
        var xMarks2 = Stepped.new(0..10000, 1000)
        var yMarks2 = Stepped.new(0..400, 100)
        axes.label(xMarks2, yMarks2, Color.black, 2, Color.black)
        axes.lineGraph(Pts, Color.blue, 2)
    }

    init() {}

    update() {}

    draw(alpha) {}
}

var Game = Main.new()
Output:

Terminal output:

Inventory sequence, first 100 elements:
 0  1  1  0  2  2  2  0  3  2  4  1  1  0  4  4  4  1  4  0
 5  5  4  1  6  2  1  0  6  7  5  1  6  3  3  1  0  7  9  5
 3  6  4  4  2  0  8  9  6  4  9  4  5  2  1  3  0  9 10  7
 5 10  6  6  3  1  4  2  0 10 11  8  6 11  6  9  3  2  5  3
 2  0 11 11 10  8 11  7  9  4  3  6  4  5  0 12 11 10  9 13

First element >=  1,000 is  1,001 at index  24,255
First element >=  2,000 is  2,009 at index  43,301
First element >=  3,000 is  3,001 at index  61,708
First element >=  4,000 is  4,003 at index  81,456
First element >=  5,000 is  5,021 at index  98,704
First element >=  6,000 is  6,009 at index 121,342
First element >=  7,000 is  7,035 at index 151,756
First element >=  8,000 is  8,036 at index 168,804
First element >=  9,000 is  9,014 at index 184,428
First element >= 10,000 is 10,007 at index 201,788


XPL0

include xpllib; \for Print

def Size = 201_790;
int Seq(Size), SeqEnd, Num, Count, N, Thresh;
[SeqEnd:= 0;
loop    [Num:= 0;
        repeat  Count:= 0;
                for N:= 0 to SeqEnd-1 do
                    if Num = Seq(N) then Count:= Count+1;
                Seq(SeqEnd):= Count;
                SeqEnd:= SeqEnd+1;
                if SeqEnd >= Size then quit;
                Num:= Num+1;
        until   Count = 0;
        ];
Thresh:= 1000;
for N:= 0 to SeqEnd-1 do
    if N < 100 then
        [Print("%3.0f", float(Seq(N)));
        if rem(N/20) = 19 then CrLf(0);
        ]
    else if Seq(N) >= Thresh then
        [Print("First element >= %5.0f: %5.0f in position %6.0f\n",
                float(Thresh), float(Seq(N)), float(N));
        if Thresh >= 10000 then return;
        Thresh:= Thresh + 1000;
        ];
]
Output:
  0  1  1  0  2  2  2  0  3  2  4  1  1  0  4  4  4  1  4  0
  5  5  4  1  6  2  1  0  6  7  5  1  6  3  3  1  0  7  9  5
  3  6  4  4  2  0  8  9  6  4  9  4  5  2  1  3  0  9 10  7
  5 10  6  6  3  1  4  2  0 10 11  8  6 11  6  9  3  2  5  3
  2  0 11 11 10  8 11  7  9  4  3  6  4  5  0 12 11 10  9 13
First element >=  1000:  1001 in position  24255
First element >=  2000:  2009 in position  43301
First element >=  3000:  3001 in position  61708
First element >=  4000:  4003 in position  81456
First element >=  5000:  5021 in position  98704
First element >=  6000:  6009 in position 121342
First element >=  7000:  7035 in position 151756
First element >=  8000:  8036 in position 168804
First element >=  9000:  9014 in position 184428
First element >= 10000: 10007 in position 201788