A071564 Smallest k such that n^8+k^8, n^4+k^4, n^2+k^2, n+k are simultaneously prime.

1, 1, 8860, 1, 6822, 601, 7912, 65093, 81430, 11383, 5066, 54667, 9618, 28149, 236, 85, 140, 953, 1260, 119, 5206, 19555, 788, 1955, 246, 7701, 170, 255, 58514, 91511, 30750, 6237, 45508, 1725, 272, 16985, 5712, 225, 81520, 1587, 54560, 4607, 7710

Offset

1,3

Links

Table of n, a(n) for n=1..43.

Mathematica

Do[k = 1; While[ !PrimeQ[n + k] || !PrimeQ[n^2 + k^2] || !PrimeQ[n^4 + k^4] || !PrimeQ[n^8 + k^8], k++ ]; Print[k], {n, 1, 45}]
sk[n_]:=Module[{k=1}, While[!AllTrue[{n^8+k^8, n^4+k^4, n^2+k^2, n+k}, PrimeQ], k++]; k]; Array[sk, 45] (* Requires Mathematica version 10 or later *) (* Harvey P. Dale, Jun 01 2017 *)

Prog

(PARI) for(n=1, 7, s=1; while(isprime(s^2+n^2)*isprime(s+n)*isprime(s^4+n^4)*isprime(s^8+n^8)==0, s++); print1(s, ", "))

Crossrefs

Sequence in context: A216926 A292572 A236031 * A031625 A046506 A116242

Adjacent sequences: A071561 A071562 A071563 * A071565 A071566 A071567

Keyword

easy,nonn

Author

Benoit Cloitre, May 30 2002

Extensions

Edited by Robert G. Wilson v, Jun 07 2002

Status

approved