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%I #5 Jul 13 2013 11:04:58
%S 2,3,5,7,121,131,151,171,232,474,535,575,666,929,999,3993,9339,11211,
%T 11311,11511,11711,12321,14741,15351,15751,16661,19291,19991,21312,
%U 22722,23632,28782,29392,32623,33233,33933,35753,36363,38383,39193
%N Palindromes for which the multiplicative digital root is a prime.
%e 575 is in the sequence because (1) it is a palindrome and (2)the multiplicative digital root is 5, which is a prime.
%t d[n_] := IntegerDigits[n]; Select[Range[39200], Reverse[y = d[#1]] == y && PrimeQ[NestWhile[Times @@ d[#] &, #1, # > 9 &]] &] (* _Jayanta Basu_, Jul 13 2013 *)
%Y Cf. A002113.
%K base,nonn
%O 1,1
%A Luc Stevens (lms022(AT)yahoo.com), Apr 16 2006
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