A244380 - OEIS

%I #10 Sep 08 2022 08:46:08

%S 48,136,172,198,222,388,718,802,844,966,1342,1356,1488,1542,1668,1708,

%T 1734,1780,1956,2008,2082,2316,2356,2394,2422,2536,2734,2844,2880,

%U 2916,2974,2982,3024,3120,3258,3364,3562,3664,3906,3930,4308,4312,4554,4566

%N Numbers k such that 1 + k + k^3 + k^5 + k^7 + k^9 + ... + k^25 is prime.

%H Vincenzo Librandi, <a href="/A244380/b244380.txt">Table of n, a(n) for n = 1..700</a>

%t Select[Range[6000], PrimeQ[Total[#^Range[1, 25, 2]] + 1] &]

%o (Magma) [n: n in [0..5500] | IsPrime(s) where s is 1+&+[n^i: i in [1..25 by 2]]];

%Y Cf. similar sequences listed in A244376.

%K nonn,easy

%O 1,1

%A _Vincenzo Librandi_, Jun 27 2014