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A217128
Numbers n such that (2n)^4 + 1 is not prime.
1
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
MATHEMATICA
Select[Range[100], ! PrimeQ[(2 #)^4 + 1] &]
PROG
(Magma) [n: n in [1..100] | not IsPrime((2*n)^4+1)];
CROSSREFS
Sequence in context: A088685 A022299 A099049 * A036668 A260997 A192242
KEYWORD
nonn,easy
AUTHOR
Vincenzo Librandi, Sep 27 2012
STATUS
approved