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%I #3 Mar 30 2012 17:31:06
%S 73,2,3,0,5,0,7,0,0,0,11,0,211,0,0,0,53,0,613,0,0,0,0,0,43,0,0,0,0,0,
%T 0,0,0,0,0,0,0,0,0,0,23,0,241,0,0,0,0,0,13,0,0,0,251,0,0,0,0,0,653,0,
%U 97,0,0,0,0,0,0,0,0,0,0,0,271,0,0,0,0,0,673,0,0,0,281,0,67,0,0,0,683,0,0,0,0
%N Smallest prime p such that p+n is twice its reversal, or 0 if impossible.
%e a(13) = 211 since 211+13 = 224 = 2*112. a(25) = 43 since 25+43 = 68 = 2*34.
%t f[n_] := Block[{k = 1}, While[p = Prime[k]; p + n != 2FromDigits[ Reverse[ IntegerDigits[ p]]] && k < 10^6, k++ ]; If[k == 10^6, 0, Prime[k]]]; Table[ f[n], {n, 75}]
%Y Cf. A099190.
%K base,nonn
%O 1,1
%A _Robert G. Wilson v_, Oct 01 2004
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