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A058780 Numbers n such that n^2 * 2^n + 1 is prime. 3
1, 2, 3, 4, 21, 30, 33, 57, 100, 142, 144, 150, 198, 225, 304, 513, 782, 858, 3638, 6076, 9297, 11037, 12135, 12876, 30180, 48470 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,2

LINKS

Table of n, a(n) for n=1..26.

Steven Harvey, Generalized HyperCullen Primes

MATHEMATICA

Do[ If[ PrimeQ[ n^2*2^n + 1 ], Print[n] ], {n, 1, 5000} ]

PROG

(PARI) is(n)=ispseudoprime(n^2*2^n+1) \\ Charles R Greathouse IV, May 22 2017

CROSSREFS

Sequence in context: A225472 A176234 A308891 * A183458 A109787 A109302

Adjacent sequences:  A058777 A058778 A058779 * A058781 A058782 A058783

KEYWORD

nonn

AUTHOR

Robert G. Wilson v, Jan 02 2001

EXTENSIONS

More terms from Herman Jamke (hermanjamke(AT)fastmail.fm), Jan 05 2008

STATUS

approved

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Last modified February 24 22:57 EST 2020. Contains 332216 sequences. (Running on oeis4.)