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A096171 Numbers n such that n^4+1 is an odd semiprime. 3
8, 10, 12, 14, 18, 22, 26, 30, 32, 36, 38, 40, 42, 50, 52, 58, 62, 68, 72, 78, 84, 86, 92, 94, 98, 100, 102, 108, 112, 114, 116, 120, 122, 124, 128, 130, 138, 146, 148, 152, 158, 162, 166, 170, 172, 176, 184, 186, 200, 212, 214, 216, 218, 222, 224, 226, 234, 250, 252 (list; graph; refs; listen; history; internal format)
OFFSET

1,1

EXAMPLE

a(1)=8 because 8^4+1=4097=17*241, a(2)=10: 10^4+1=10001=73*137.

PROG

(PARI) isA096171(n) = {local(m); m=n^4+1; (m%2==1)&&(bigomega(m)==2)} [From Michael B. Porter (michael_b_porter(AT)yahoo.com), Feb 02 2010]

CROSSREFS

Cf. A000068 n^4+1 is prime, A037896 primes of the form n^4+1, A096169 (n^4+1)/2 is prime, A069170 primes of the form (n^4+1)/2, A096172 largest prime factor of n^4+1, A046388.

Sequence in context: A020744 A008557 A161425 * A154786 A158273 A157939

Adjacent sequences:  A096168 A096169 A096170 * A096172 A096173 A096174

KEYWORD

nonn

AUTHOR

Hugo Pfoertner (hugo(AT)pfoertner.org), Jun 19 2004

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Last modified February 17 14:50 EST 2012. Contains 206050 sequences.