Successive prime differences: Difference between revisions

=={{header|Arturo}}==

<lang rebol>LIM: 1000000

findDiffs: function [r][

if r=[1] -> return [[2 3]]

i: 3

tupled: map 0..dec size r 'x -> fold slice r 0 x [a b][a+b]

diffs: new []

while [i < LIM][

if prime? i [

prset: map tupled 't -> i + t

if every? prset 'elem -> prime? elem [

'diffs ++ @[@[i] ++ prset]

]

]

i: i + 2

]

diffs: filter diffs 'dd [

some? range (first dd)+1 (last dd)-1 'x -> and? [prime? x][not? contains? dd x]

]

return diffs

]

loop [[2] [1] [2 2] [2 4] [4 2] [6 4 2]] 'rng [

print ["Differences of" join.with:", " to [:string] rng]

diffs: findDiffs rng

print ["\tFirst: " join.with:" " to [:string] first diffs]

print ["\tLast: " join.with:" " to [:string] last diffs]

print ["\tCount: " size diffs]

]</lang>

{{out}}

<pre>Differences of 2

First: 3 5

Last: 999959 999961

Count: 8169

Differences of 1

First: 2 3

Last: 2 3

Count: 1

Differences of 2, 2

First: 3 5 7

Last: 3 5 7

Count: 1

Differences of 2, 4

First: 5 7 11

Last: 999431 999433 999437

Count: 1393

Differences of 4, 2

First: 7 11 13

Last: 997807 997811 997813

Count: 1444

Differences of 6, 4, 2

First: 31 37 41 43

Last: 997141 997147 997151 997153

Count: 306</pre>