A121817 Numbers m such that 23 + 36*m*(m+1) is prime.

0, 2, 4, 5, 7, 12, 14, 15, 27, 30, 32, 34, 40, 47, 49, 50, 57, 60, 62, 67, 72, 75, 82, 85, 89, 95, 97, 102, 104, 105, 109, 110, 119, 135, 140, 162, 175, 177, 180, 182, 187, 189, 194, 200, 214, 219, 222, 225, 235, 239, 242, 244, 247, 254, 257, 259, 265, 277, 279, 280

Offset: 1

Author

Zak Seidov, Sep 09 2006

Keywords

• nonn

Comments

All terms of A121250 (numbers n such that n^2+14 is prime) are of the form n = 3+6*m, m = 0, 1, .... Hence n^2 + 14 = 23 + 36*m(m+1): these values of m are in this sequence.

Crossrefs

Cf. A121250.

Programs

Mathematica

Select[Range[0,300], PrimeQ[23 + 36*#(1+#) ]&]

PARI

select( is_A121817(n)=isprime(23+36*(n+1)*n), [0..299]) \\ M. F. Hasler, May 25 2019

Extensions

Edited by M. F. Hasler, May 25 2019