A107295 Numbers k such that prime(k^2) - k^2 is prime.

2, 4, 12, 14, 20, 42, 48, 56, 60, 88, 104, 120, 126, 134, 138, 160, 164, 182, 186, 204, 226, 254, 270, 276, 312, 316, 330, 336, 350, 382, 408, 410, 414, 422, 438, 448, 450, 480, 492, 494, 502, 522, 546, 568, 580, 596, 620, 624, 640, 650, 690, 696

Offset: 1

Author

Zak Seidov, May 20 2005

Keywords

• nonn

Examples

			88 is in the sequence because prime(88^2) - 88^2 = prime(7744) - 7744 = 78977 - 7744 = 71233 = prime(7051).
		

Crossrefs

Cf. A064269 (prime(n)-n is prime), A141129 (prime(n^2)-n^2).

Programs

Mathematica

Select[Range[700],PrimeQ[Prime[#^2]-#^2]&] (* Harvey P. Dale, Jun 20 2015 *)

PARI

isok(n) = isprime(prime(n^2) - n^2); \\ Michel Marcus, Oct 09 2013

Extensions

More terms from Michel Marcus, Oct 09 2013