A209777 Number of q in the range 0<=q<=n for which k(n)+k(q) is prime, with k(n) := n*(n+1)^2/2.

1, 1, 0, 1, 0, 2, 1, 0, 0, 3, 0, 1, 2, 0, 0, 2, 1, 3, 1, 0, 0, 9, 1, 0, 2, 2, 0, 2, 1, 2, 4, 0, 0, 6, 1, 1, 5, 4, 1, 3, 2, 3, 2, 0, 0, 15, 0, 2, 2, 3, 3, 7, 1, 4, 2, 1, 3, 17, 2, 1, 6, 5, 1, 4, 2, 8, 3, 0, 0, 7, 2, 3, 9, 3, 1, 2, 0, 9, 1, 0, 2, 21, 1, 4, 6, 9, 2, 5, 2, 4, 6, 3, 3, 16, 2, 2, 4, 5, 1, 2

Offset: 1

Author

Gerasimov Sergey, Mar 27 2012

Keywords

• nonn

Examples

			a(6)=2 because 147+2 and 147+50 are primes;
a(10)=3 because 605+2, 605+224 and 605+324 are primes.
		

Crossrefs

Cf. A006002, A130504.

Extensions

Corrected by R. J. Mathar, Mar 30 2012