A165439 - OEIS

%I #12 Sep 08 2022 08:45:47

%S 2,5,7,11,13,17,19,23,31,37,41,43,53,59,61,67,71,73,89,101,103,107,

%T 109,113,127,131,139,149,151,157,163,167,179,181,193,197,199,211,223,

%U 229,233,239,241,251,257,269,271,283,293,307,311,313,331,337,347,359,373

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

%H Bruno Berselli, <a href="/A165439/b165439.txt">Table of n, a(n) for n = 1..1000</a>

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

%t Select[Prime[Range[200]],PrimeQ[2 Total[IntegerDigits[#]]+3]&] (* _Harvey P. Dale_, Jul 14 2011 *)

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

%Y Cf. A165440, A007605.

%K nonn,base

%O 1,1

%A _Vincenzo Librandi_, Sep 19 2009

%E Keyword:base added by _R. J. Mathar_, Oct 12 2009