A172988 Primes p such that either p-3 or p-6 is prime.

5, 11, 13, 17, 19, 23, 29, 37, 43, 47, 53, 59, 67, 73, 79, 89, 103, 107, 109, 113, 137, 157, 163, 173, 179, 197, 199, 229, 233, 239, 257, 263, 269, 277, 283, 313, 317, 337, 353, 359, 373, 379, 389, 439, 449, 463, 467, 509, 547, 563, 569, 577, 593, 599, 607, 613

Offset: 1

Author

Juri-Stepan Gerasimov, Feb 07 2010

Keywords

• nonn

Comments

5 is the only prime p for which p-3 is prime, since p-3 is even for any odd prime and 2 is the only even prime. - Harvey P. Dale, Apr 03 2019

Crossrefs

Cf. A046117, A067831.

Programs

Mathematica

Select[Prime[Range[150]],AnyTrue[#+{-3,-6},PrimeQ]&] (* Requires Mathematica version 10 or later *) (* or *) Join[{5},Select[Prime[ Range[ 3,150]],PrimeQ[#-6]&]] (* see Comment *) (* Harvey P. Dale, Apr 03 2019 *)

Formula

a(n)=A046117(n+1).

Extensions

449 inserted by R. J. Mathar, Mar 09 2010