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%I #5 Mar 31 2012 10:26:00
%S 2,131,11311,1114111,111181111,11112721111,1111118111111,
%T 111111151111111,11111112521111111,1111111111111111111,
%U 111111111161111111111,11111111111111111111111
%N Smallest zero-free palindromic prime of 2n + 1 digits.
%t a[n_] := Block[{k = (10^(n + 1) - 1)/9}, While[m = FromDigits[ Join[ IntegerDigits[k], Reverse[ Drop[ IntegerDigits[k], -1]]]]; !PrimeQ[m], k++ ]; m]; Table[ a[n], {n, 0, 13}]
%Y Cf. A028989.
%K nonn,base
%O 0,1
%A _Lekraj Beedassy_, Jun 21 2002
%E Edited by _Robert G. Wilson v_, Jun 21 2002
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