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%I #9 Mar 15 2015 20:02:44
%S 17,491,1823,6883,183661,757063,9642461,10398683,11948737,61241363,
%T 125644177,141037697,168598249,329147719,1507060573,2936125141,
%U 24257906011,74038127803,863209344623,1167992076341
%N Primes containing as substring the string reversal of their index.
%C a(21) > 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[ Prime[n]]], {n, 10^8}] (* _Robert G. Wilson v_, Jun 28 2005 *)
%Y Corresponding indices form A109304.
%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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