A244379 Numbers k such that 1 + k + k^3 + k^5 + k^7 + k^9 + ... + k^21 is prime.

2, 30, 56, 122, 216, 246, 248, 318, 552, 846, 948, 1100, 1128, 1148, 1200, 1296, 1308, 1416, 1716, 1812, 1818, 1920, 2040, 2166, 2196, 2210, 2582, 2592, 2672, 2696, 2828, 2862, 2886, 2970, 3150, 3192, 3378, 3396, 3492, 3522, 3626, 3782, 3998, 4040, 4070

Offset: 1

Author

Vincenzo Librandi, Jun 27 2014

Keywords

• nonn
• easy

Links

• Vincenzo Librandi, Table of n, a(n) for n = 1..700

Crossrefs

Cf. similar sequences listed in A244376.

Programs

Magma

[n: n in [0..4500] | IsPrime(s) where s is 1+&+[n^i: i in [1..21 by 2]]];

Mathematica

Select[Range[5000], PrimeQ[Total[#^Range[1, 21, 2]] + 1]&]

Sage

i,n = var('i,n')
[n for n in (1..4100) if is_prime(1+(n^(2*i+1)).sum(i,0,10))] # Bruno Berselli, Jun 27 2014