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A110965 Numbers k such that 23*k^2 + 25 is prime. 0
6, 18, 36, 42, 48, 66, 108, 126, 174, 198, 204, 216, 234, 246, 252, 312, 342, 372, 402, 426, 504, 516, 546, 564, 582, 618, 624, 642, 666, 702, 708, 732, 768, 774, 822, 852, 888, 906, 924, 936, 948, 966, 972, 978, 984, 996, 1008, 1014, 1032, 1062, 1092, 1098 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

LINKS

Table of n, a(n) for n=1..52.

Emre Alkan, Alexandru Zaharescu, Nonvanishing of the Ramanujan tau function in short intervals, International Journal of Number Theory, Vol. 1, No. 1 (2005) 45-51.

EXAMPLE

23*198^2 + 25 = 901717 (prime).

PROG

(MAGMA) [ n: n in [0..1500] | IsPrime( 23*n^2 + 25) ] // Vincenzo Librandi, Jan 31 2011

(PARI) is(n)=isprime(23*n^2+25) \\ Charles R Greathouse IV, Jun 13 2017

CROSSREFS

Sequence in context: A038343 A271123 A271303 * A111147 A333821 A328586

Adjacent sequences:  A110962 A110963 A110964 * A110966 A110967 A110968

KEYWORD

nonn,easy

AUTHOR

Parthasarathy Nambi, Sep 26 2005

EXTENSIONS

Edited by Don Reble, Nov 08 2005

STATUS

approved

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Last modified September 24 12:23 EDT 2021. Contains 347642 sequences. (Running on oeis4.)