Esthetic numbers: Difference between revisions

=={{header|J}}==

Implementation (brute force):

<lang J>isesthetic=: 10&$: :(1 */ .=2 |@-/\ #.inv)"0

gen=: {{r=.$k=.1 while.y>#r do. r=.r,k#~u k

k=.1+({:k)+i.2*#k end.y{.r}}</lang>

Task examples:

<lang J>tobase=: (a.{~;48 97(+ i.)each 10 26) {~ #.inv

taskB=: {{;:inv y tobase&.> (<:4*y)}. y&isesthetic gen 6*y}}

taskB 2

10101010 101010101 1010101010 10101010101 101010101010

taskB 3

1210 1212 2101 2121 10101 10121 12101

taskB 4

323 1010 1012 1210 1212 1232 2101 2121 2123

taskB 5

323 343 432 434 1010 1012 1210 1212 1232 1234 2101

taskB 6

343 345 432 434 454 543 545 1010 1012 1210 1212 1232 1234

taskB 7

345 432 434 454 456 543 545 565 654 656 1010 1012 1210 1212 1232

taskB 8

432 434 454 456 543 545 565 567 654 656 676 765 767 1010 1012 1210 1212

taskB 9

434 454 456 543 545 565 567 654 656 676 678 765 767 787 876 878 1010 1012 1210

taskB 10

454 456 543 545 565 567 654 656 676 678 765 767 787 789 876 878 898 987 989 1010 1012

taskB 11

456 543 545 565 567 654 656 676 678 765 767 787 789 876 878 898 89a 987 989 9a9 a98 a9a 1010

taskB 12

543 545 565 567 654 656 676 678 765 767 787 789 876 878 898 89a 987 989 9a9 9ab a98 a9a aba ba9 bab

taskB 13

545 565 567 654 656 676 678 765 767 787 789 876 878 898 89a 987 989 9a9 9ab a98 a9a aba abc ba9 bab bcb cba

taskB 14

565 567 654 656 676 678 765 767 787 789 876 878 898 89a 987 989 9a9 9ab a98 a9a aba abc ba9 bab bcb bcd cba cbc cdc

taskB 15

567 654 656 676 678 765 767 787 789 876 878 898 89a 987 989 9a9 9ab a98 a9a aba abc ba9 bab bcb bcd cba cbc cdc cde dcb dcd

taskB 16

654 656 676 678 765 767 787 789 876 878 898 89a 987 989 9a9 9ab a98 a9a aba abc ba9 bab bcb bcd cba cbc cdc cde dcb dcd ded def edc

(#~ isesthetic) 1000+i.1000

1010 1012 1210 1212 1232 1234</lang>

Stretch goal:

<lang J> $e=: (#~ isesthetic) x:1e8+i.1+3e7

126

q:126

2 3 3 7

14 9$e

101010101 101010121 101010123 101012101 101012121 101012123 101012321 101012323 101012343

101012345 101210101 101210121 101210123 101212101 101212121 101212123 101212321 101212323

101212343 101212345 101232101 101232121 101232123 101232321 101232323 101232343 101232345

101234321 101234323 101234343 101234345 101234543 101234545 101234565 101234567 121010101

121010121 121010123 121012101 121012121 121012123 121012321 121012323 121012343 121012345

121210101 121210121 121210123 121212101 121212121 121212123 121212321 121212323 121212343

121212345 121232101 121232121 121232123 121232321 121232323 121232343 121232345 121234321

121234323 121234343 121234345 121234543 121234545 121234565 121234567 123210101 123210121

123210123 123212101 123212121 123212123 123212321 123212323 123212343 123212345 123232101

123232121 123232123 123232321 123232323 123232343 123232345 123234321 123234323 123234343

123234345 123234543 123234545 123234565 123234567 123432101 123432121 123432123 123432321

123432323 123432343 123432345 123434321 123434323 123434343 123434345 123434543 123434545

123434565 123434567 123454321 123454323 123454343 123454345 123454543 123454545 123454565

123454567 123456543 123456545 123456565 123456567 123456765 123456767 123456787 123456789</lang>

Note: in some of these cases, it would be more efficient to take a generative approach (generating sequences of digits from a base digit, rather than generating sequential integers discarding those which are not suitable).