A176002 Numbers n such that 15*prime(n)+{-4,-2,2,4} are all primes.

4, 6, 34, 176, 608, 1023, 1338, 1377, 1555, 1980, 2054, 2850, 2893, 3061, 3263, 3572, 3977, 4029, 4244, 4405, 6099, 6548, 7203, 7348, 7350, 7572, 7574, 9028, 10657, 11976, 12215, 12874, 13247, 13388, 13432, 14537, 14813, 15115, 15412, 15509

Offset: 1

Author

Juri-Stepan Gerasimov, Apr 11 2010

Keywords

• nonn

Comments

Numbers n such that 15*prime(n)-4, 15*prime(n)-2, 15*prime(n)+2 and 15*prime(n)+4 are primes.

Examples

			a(1)=4 because 15*prime(4)-4=101, 15*prime(4)-2=103, 15*prime(4)+2=107 and 15*prime(4)+4=109.
		

Crossrefs

Cf. A112540, A173037, A173092.

Programs

Mathematica

p15Q[n_]:=And@@PrimeQ/@(15 Prime[n]+{-4,-2,2,4}); Select[Range[16000], p15Q]  (* Harvey P. Dale, Mar 20 2011 *)

Formula

A000040(a(n))=A112540(k).

Extensions

More terms from R. J. Mathar, Apr 16 2010