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A244379
Numbers k such that 1 + k + k^3 + k^5 + k^7 + k^9 + ... + k^21 is prime.
2
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
1,1
LINKS
MATHEMATICA
Select[Range[5000], PrimeQ[Total[#^Range[1, 21, 2]] + 1]&]
PROG
(Magma) [n: n in [0..4500] | IsPrime(s) where s is 1+&+[n^i: i in [1..21 by 2]]];
(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
CROSSREFS
Cf. similar sequences listed in A244376.
Sequence in context: A078208 A105403 A134644 * A189100 A085637 A193177
KEYWORD
nonn,easy
AUTHOR
Vincenzo Librandi, Jun 27 2014
STATUS
approved