A087090 Positive numbers n such that p=n^2+n+41 and p+2 are twin primes.

0, 5, 12, 15, 17, 20, 24, 35, 45, 50, 59, 75, 90, 92, 105, 110, 119, 120, 132, 134, 167, 174, 182, 222, 225, 230, 264, 269, 285, 320, 335, 339, 362, 365, 372, 390, 419, 434, 437, 455, 462, 470, 479, 495, 539, 540, 549, 572, 594, 705, 710, 714, 759, 785, 789

Offset: 1

Author

Zak Seidov, Aug 08 2003

Keywords

• nonn

Examples

			5 is in the sequence because 71 and 73 are twin primes.
		

Links

• Pierre CAMI and Charles R Greathouse IV, Table of n, a(n) for n = 1..10000 (first 2028 terms from Cami)

Crossrefs

Cf. A007634, A087091.

Programs

Mathematica

Select[Range[0,800],AllTrue[#^2 +#+{41,43},PrimeQ]&] (* The program uses the AllTrue function from Mathematica version 10 *) (* Harvey P. Dale, May 20 2016 *)

PARI

isok(n) = isprime(n^2+n+41) && isprime(n^2+n+43); \\ Michel Marcus, Oct 03 2013