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%I A157677
%S A157677 23,29,61,67,83,101,103,107,109,163,233,239,283,293,307,347,349,401,409,
%T A157677 431,439,443,449,499,503,509,563,569,601,607,613,617,619,653,659,677,
%U A157677 683,701,709,743,809,907,929,941,1009,1013,1019,1021,1031,1033,1039
%N A157677 Prime numbers p such that p + (product of digits) is also prime.
%C A157677 If p contains a zero, then a(p) is trivial.
%F A157677 a(p) = p + DigitProduct(p)
%e A157677 83 is prime, and a(83) = 83 + (8)(3) = 89 which is also prime. 103 is 
               prime, and a(103) = 103 + (1)(0)(3) = 103 which is prime.
%p A157677 a := proc (n) local nn: nn := convert(ithprime(n), base, 10): if isprime(ithprime(n)+product(nn[j], 
               j = 1 .. nops(nn))) = true then ithprime(n) else end if end proc: 
               seq(a(n), n = 1 .. 180); [From Emeric Deutsch (deutsch(AT)duke.poly.edu), 
               Mar 08 2009]
%Y A157677 Sequence in context: A097436 A063980 A046124 this_sequence A092518 A110584 
               A115396
%Y A157677 Adjacent sequences: A157674 A157675 A157676 this_sequence A157678 A157679 
               A157680
%K A157677 nonn,base
%O A157677 1,1
%A A157677 Kyle D. Balliet (kdballie(AT)bloomu.edu), Mar 04 2009
%E A157677 More terms from Emeric Deutsch (deutsch(AT)duke.poly.edu), Mar 08 2009

    
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Last modified December 5 23:38 EST 2009. Contains 170428 sequences.


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