A126911 Numbers k such that 1 + k^2 + k^4 + k^6 + k^8 + k^10 + k^12 + k^13 is prime.

10, 24, 60, 148, 174, 180, 268, 274, 280, 294, 346, 472, 484, 516, 522, 598, 654, 804, 834, 856, 858, 898, 994, 1012, 1036, 1054, 1066, 1102, 1168, 1272, 1294, 1338, 1342, 1368, 1420, 1462, 1500, 1536, 1564, 1588, 1608, 1624, 1710, 1746, 1786, 1792, 1822, 1992

Offset: 1

Author

Artur Jasinski, Dec 31 2006

Keywords

• nonn
• easy

Links

• Daniel Starodubtsev, Table of n, a(n) for n = 1..10000

Crossrefs

Cf. A049407, A124175 A124176 A124177, A124178, A124179, A124180, A124181, A126908-A126916.

Programs

Mathematica

a = {}; Do[If[PrimeQ[1 + n^2 + n^4 + n^6 + n^8 + n^10 + n^12 + n^13], AppendTo[a, n]], {n, 1, 1400}]; a

PARI

is(n)=isprime(1+n^2+n^4+n^6+n^8+n^10+n^12+n^13) \\ Charles R Greathouse IV, Jun 13 2017

Python

from sympy import isprime
def ok(k): return isprime(1+sum(k**i for i in [2, 4, 6, 8, 10, 12, 13]))
print([k for k in range(2000) if ok(k)]) # Michael S. Branicky, Oct 24 2021