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A096169
Odd n such that (n^4+1)/2 is prime.
6
3, 5, 7, 11, 13, 17, 21, 23, 29, 35, 39, 57, 61, 65, 71, 73, 81, 103, 105, 113, 115, 119, 129, 153, 165, 169, 171, 199, 203, 205, 251, 259, 267, 275, 309, 313, 317, 333, 337, 339, 353, 363, 403, 405, 415, 419, 431, 445, 449, 453, 455, 463, 471, 477, 479, 487
OFFSET
1,1
EXAMPLE
a(1)=3 because (3^4+1)/2=82/2=41 is prime.
MATHEMATICA
Select[Range[1, 501, 2], PrimeQ[(#^4+1)/2]&] (* Harvey P. Dale, Jun 04 2011 *)
PROG
(Magma) [ n: n in [0..2500] | IsPrime((n^4+1) div 2) ]; // Vincenzo Librandi, Apr 15 2011
CROSSREFS
Cf. A000068 n^4+1 is prime, A037896 primes of the form n^4+1, A096170 primes of the form (n^4+1)/2, A096171 n^4+1 is an odd semiprime, A096172 largest prime factor of n^4+1.
Sequence in context: A069467 A309739 A249876 * A225526 A090670 A074832
KEYWORD
nonn
AUTHOR
Hugo Pfoertner, Jun 19 2004
STATUS
approved