A182048 Numbers n such that 16n^2-2n-1 and 16n^2+2n-1 are both primes.

1, 2, 3, 5, 6, 7, 10, 13, 19, 29, 32, 36, 62, 63, 70, 75, 78, 85, 93, 96, 102, 107, 109, 119, 123, 128, 145, 158, 164, 174, 177, 190, 192, 197, 219, 241, 247, 252, 280, 284, 299, 304, 318, 335, 340, 344, 354, 361, 374, 377, 382, 385, 387, 427, 434, 439, 440

Offset: 1

Author

Gerasimov Sergey, Apr 08 2012

Keywords

• nonn

Examples

			a(1)=1 because 16*1^2-2*1-1=13 is prime and 16*1^2+2*1-1=17 is prime.
		

Links

• Harvey P. Dale, Table of n, a(n) for n = 1..3500

Crossrefs

Cf. A171748, A089637.

Programs

Mathematica

Select[Range[500], PrimeQ[16 #^2 - 2 # - 1] && PrimeQ[16 #^2 + 2 # - 1] &] (* T. D. Noe, Apr 16 2012 *)
Select[Range[500],AllTrue[16#^2-1+{2#,-2#},PrimeQ]&] (* The program uses the AllTrue function from Mathematica version 10 *) (* Harvey P. Dale, Jan 01 2018 *)

Extensions

Corrected and extended by T. D. Noe, Apr 16 2012