A165439 Primes p such that 3+2*(sum of digits of p) is also a prime.

2, 5, 7, 11, 13, 17, 19, 23, 31, 37, 41, 43, 53, 59, 61, 67, 71, 73, 89, 101, 103, 107, 109, 113, 127, 131, 139, 149, 151, 157, 163, 167, 179, 181, 193, 197, 199, 211, 223, 229, 233, 239, 241, 251, 257, 269, 271, 283, 293, 307, 311, 313, 331, 337, 347, 359, 373

Offset: 1

Author

Vincenzo Librandi, Sep 19 2009

Keywords

• nonn
• base
• changed

Examples

			331 is in the sequence because 3+3+1=7 and 2*7+3=17 is prime.
		

Links

• Bruno Berselli, Table of n, a(n) for n = 1..1000

Crossrefs

Cf. A165440, A007605.

Programs

Magma

[ p: p in PrimesUpTo(400) | IsPrime(q) where q is 3+2*(&+Intseq(p))];  // Bruno Berselli, Jul 15 2011

Mathematica

Select[Prime[Range[200]],PrimeQ[2 Total[IntegerDigits[#]]+3]&] (* Harvey P. Dale, Jul 14 2011 *)

Extensions

Keyword:base added by R. J. Mathar, Oct 12 2009