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A121979 Numbers n such that (2n^2)^4 + 1 is prime. 1
1, 11, 12, 20, 24, 27, 28, 34, 40, 44, 61, 74, 79, 82, 95, 96, 119, 131, 136, 147, 148, 156, 164, 170, 173, 180, 187, 209, 211, 238, 252, 255, 269, 279, 299, 328, 337, 340, 343, 371, 379, 380, 388, 397, 413, 452, 462, 473, 476, 483, 516, 522, 527, 530, 539, 572 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,2

COMMENTS

Corresponding primes of the form (2n^2)^4 + 1 are {17, 3429742097, 6879707137, 409600000001, ...}.

There are consecutive twin pairs {a(n),a(n+1)} = {11,12}, {27,28}, {95,96},{147,148}, ...

LINKS

G. C. Greubel, Table of n, a(n) for n = 1..5000

MATHEMATICA

Select[Range[1000], PrimeQ[(2*#1^2)^4+1]&]

PROG

(PARI) is(n)=isprime((2*n^2)^4+1) \\ Charles R Greathouse IV, Jun 13 2017

CROSSREFS

Cf. A000068.

Sequence in context: A105744 A092096 A057303 * A109372 A066686 A125887

Adjacent sequences:  A121976 A121977 A121978 * A121980 A121981 A121982

KEYWORD

nonn,easy

AUTHOR

Alexander Adamchuk, Sep 10 2006

STATUS

approved

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Last modified August 17 06:56 EDT 2018. Contains 313810 sequences. (Running on oeis4.)