A103803 Primes p such that both 2p - 15 and 2p + 15 are primes.

11, 13, 19, 23, 29, 37, 41, 43, 47, 61, 71, 83, 89, 107, 113, 127, 139, 149, 191, 197, 223, 281, 293, 331, 379, 419, 421, 461, 463, 491, 499, 503, 523, 569, 593, 601, 653, 719, 733, 769, 797, 811, 821, 839, 881, 887, 1049, 1063, 1129, 1163, 1181, 1213, 1231

Offset: 1

Author

Zak Seidov, Feb 16 2005

Keywords

• nonn

Links

• Harvey P. Dale, Table of n, a(n) for n = 1..1000

Crossrefs

Cf. A103802.

Programs

Magma

[p: p in PrimesUpTo(3200)| IsPrime(2*p+15) and IsPrime(2*p-15) ]; // Vincenzo Librandi, Jan 28 2011

Mathematica

Select[Range[11,2000], PrimeQ[ # ] && PrimeQ[2# + 15] && PrimeQ[2# - 15] &]
Select[Prime[Range[2,250]],And@@PrimeQ[2#+{15,-15}]&] (* Harvey P. Dale, May 21 2013 *)

Formula

p, 2p-15 and 2p+15 all are positive and are primes (hence we omit p=2).