A166567 - OEIS

%I #7 Sep 14 2013 15:12:21

%S 3,13,17,31,53,59,71,103,107,149,167,211,233,239,251,257,293,347,383,

%T 389,419,431,479,491,503,509,521,563,569,587,617,653,659,677,701,743,

%U 761,839,857,929,941,947,983,1021,1049,1061,1151,1193,1201

%N Primes p such that sum of digits - 1 is prime.

%H Vincenzo Librandi, <a href="/A166567/b166567.txt">Table of n, a(n) for n = 1..1000</a>

%e 13 belongs to this sequence because 3+1-1=2 is prime; 17 because 1+7-1=7; 233 because 2+3+3-1=7; 653 because 6+5+3-1=13.

%t Select[Prime[Range[200]], PrimeQ[Plus@@ IntegerDigits[#] - 1]&] (* _Vincenzo Librandi_, Sep 14 2012 *)

%K nonn,base

%O 1,1

%A _Vincenzo Librandi_, Oct 28 2009