A166566 - OEIS

%I #10 Sep 14 2013 15:08:53

%S 3,13,23,29,31,41,43,61,67,83,89,113,127,131,163,167,181,223,233,239,

%T 241,269,271,277,283,293,311,347,349,383,421,431,439,443,457,461,463,

%U 467,479,487,523,541,547,563,569,613,617,619,631,641,643,647,653,659

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

%H Vincenzo Librandi, <a href="/A166566/b166566.txt">Table of n, a(n) for n = 1..1000</a>

%e 23 is in sequence because 2*3-1=5; 83 because 8*3-1=23; 163 because 1*6*3-1=17.

%t Select[Prime[Range[150]], PrimeQ[Times@@IntegerDigits[#] - 1]&] (* _Vincenzo Librandi_, Sep 14 2012 *)

%K nonn,base

%O 1,1

%A _Vincenzo Librandi_, Oct 28 2009

%E Corrected (3, 29 inserted) by _R. J. Mathar_, Nov 30 2009