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A113536 Numbers k such that k^2 + 13 is prime. 10
0, 2, 4, 10, 12, 16, 18, 28, 40, 42, 44, 46, 60, 68, 72, 82, 84, 88, 94, 108, 110, 114, 116, 122, 126, 142, 144, 152, 158, 180, 192, 194, 198, 200, 220, 222, 264, 266, 268, 282, 284, 296, 298, 332, 336, 340, 354, 378, 380, 418, 420, 430, 434, 446, 464, 466, 486 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,2

LINKS

G. C. Greubel, Table of n, a(n) for n = 1..1000

EXAMPLE

If n=40 then n^2 + 13 = 1613 (prime), so 40 is in the sequence.

MATHEMATICA

With[{k=13}, Select[Range[1000], PrimeQ[ #^2+k]&]]

PROG

(PARI) is(n)=isprime(n^2+13) \\ Charles R Greathouse IV, Feb 17 2017

CROSSREFS

Other cases: A005574 k=1, A067201 k=2, A049422 k=3, A007591 k=4, A078402 k=5, A114269-A114275 k=6-12.

Sequence in context: A278465 A129412 A266115 * A081887 A085344 A288225

Adjacent sequences:  A113533 A113534 A113535 * A113537 A113538 A113539

KEYWORD

nonn

AUTHOR

Zak Seidov, Jan 13 2006

EXTENSIONS

Edited by R. J. Mathar, Aug 07 2008

STATUS

approved

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Last modified February 17 17:47 EST 2019. Contains 320222 sequences. (Running on oeis4.)