A217128 Numbers n such that (2n)^4 + 1 is not prime.

4, 5, 6, 7, 9, 11, 13, 15, 16, 18, 19, 20, 21, 22, 25, 26, 29, 30, 31, 32, 33, 34, 35, 36, 38, 39, 42, 43, 46, 47, 48, 49, 50, 51, 52, 54, 55, 56, 57, 58, 60, 61, 62, 63, 64, 65, 67, 68, 69, 72, 73, 74, 75, 76, 78, 79, 81, 83, 84, 85, 86, 88, 89, 91, 92, 93, 94, 95, 96, 98, 100

Offset

1,1

Links

Vincenzo Librandi, Table of n, a(n) for n = 1..1000

Mathematica

Select[Range[100], ! PrimeQ[(2 #)^4 + 1] &]

Prog

(Magma) [n: n in [1..100] | not IsPrime((2*n)^4+1)];

Crossrefs

Cf. A000059, A037896.

Sequence in context: A088685 A022299 A099049 * A036668 A260997 A192242

Adjacent sequences: A217125 A217126 A217127 * A217129 A217130 A217131

Keyword

nonn,easy

Author

Vincenzo Librandi, Sep 27 2012

Status

approved