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A276471 Numbers m of the form 2*k^2 - 61 which are +-1 times a prime. 0
-61, -59, -53, -43, -29, -11, 11, 37, 67, 101, 139, 181, 227, 277, 331, 389, 587, 661, 739, 821, 907, 997, 1091, 1291, 1621, 1861, 1987, 2251, 2389, 2531, 2677, 3301, 3467, 3637, 3989, 4357, 4547, 5347, 5557, 6211, 7877, 8389, 9187, 9461, 9739, 10597, 10891, 11491, 12107, 12421, 12739 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

Note that -61 = (-1)*61 is not a prime. - N. J. A. Sloane, Nov 13 2020

LINKS

Table of n, a(n) for n=1..51.

EXAMPLE

2*(0)^2 - 61 = -61, and 61 is a prime

2*(1)^2 - 61 = -59, and 59 is a prime

PROG

(PARI) is(n)=isprime(abs(n)) && n%2 && issquare((n-61)/2) \\ Charles R Greathouse IV, Sep 13 2016

CROSSREFS

Sequence in context: A303687 A033381 A204748 * A122568 A075028 A258158

Adjacent sequences: A276468 A276469 A276470 * A276472 A276473 A276474

KEYWORD

sign

AUTHOR

Charles Kusniec, Sep 12 2016

EXTENSIONS

More terms from Charles R Greathouse IV, Sep 13 2016

Definition revised by N. J. A. Sloane, Nov 13 2020

STATUS

approved

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Last modified March 20 21:56 EDT 2023. Contains 361391 sequences. (Running on oeis4.)