A224856 Numbers n such that 90*n + 29 and 90*n + 31 are twin primes.
0, 6, 7, 11, 14, 28, 30, 33, 37, 39, 47, 53, 61, 65, 74, 75, 76, 77, 84, 88, 91, 110, 128, 139, 152, 158, 170, 179, 180, 194, 195, 201, 215, 216, 228, 229, 251, 271, 282, 305, 308, 312, 334, 336, 345, 362, 366, 368, 370, 373, 383, 384, 410, 411, 413, 427, 450
Offset: 1
Programs
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Maple
a:= proc(n) option remember; local k; for k from 1+ `if`(n=1, -1, a(n-1)) while not (isprime(29+(90*k)) and isprime(31+(90*k))) do od; k end: seq(a(n), n=1..100); # Alois P. Heinz, Jul 23 2013 -
Mathematica
Select[Range[0, 499], PrimeQ[90# + 29] && PrimeQ[90# + 31] &] (* copied from: Alonso del Arte, Jul 22 2013 *)
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