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%I #9 Mar 15 2015 20:02:12
%S 7,94,281,886,16638,60757,642469,689301,784911,3631421,7144652,
%T 7967301,9428958,17741923,75060705,141521639,1060975242,3087218304,
%U 32644390236,43670299761
%N Numbers n such that string reversal of n is a substring of n-th prime.
%C a(21) > pi(2*10^12). [From _Donovan Johnson_, May 08 2010]
%e 94th prime, 491, contains 49 = the string reversal of its index;
%e 281st prime, 1823, contains 182 = the string reversal of its index;
%e 7144652nd prime, 125644177, contains 2564417 = the string reversal of its index; etc.
%t fQ[n_] := StringPosition[ ToString[ Prime[n]], StringReverse[ ToString[n]]] != {}; Do[ If[ fQ[n], Print[n]], {n, 107350907, 2 10^9}] (* _Robert G. Wilson v_, Jun 28 2005 *)
%Y Corresponding primes form A109305.
%K base,nonn
%O 1,1
%A _Zak Seidov_, Jun 25 2005
%E a(14)-a(16) from _Robert G. Wilson v_, Jun 28 2005
%E a(17)-a(20) from _Donovan Johnson_, May 08 2010
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