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%I #10 Sep 09 2015 05:31:43
%S 2,3,5,7,2,2,5,7,10,11,7,11,13,14,16,19,22,23,19,20,5,7,8,7,8,10,13,
%T 14,11,16,17,13,17,16,17,14,17,19,20,20,25,19,22,23,28,29,7,8,10,13,
%U 14,8,13,13,14,17,19,22,16,17,19,23,20,23,22,25,22,23,29
%N Sum of digits of n-th palindromic prime.
%H Shyam Sunder Gupta, <a href="/A230199/b230199.txt">Table of n, a(n) for n = 1..5953</a>
%F a(n) = A007953(A002385(n)). - _R. J. Mathar_, Sep 09 2015
%e a(6) =2, since sum of digits of 6th palindromic prime i.e. 101 is 2.
%t a = {}; Do[z = n*10^(IntegerLength[n] - 1) +
%t FromDigits@Rest@Reverse@IntegerDigits[n]; If[PrimeQ[z], s = Apply[Plus, IntegerDigits[z]]; AppendTo[a, s]], {n, 1, 10^5}]; Insert[a, 2, 5]
%t palQ[n_]:=Module[{idn=IntegerDigits[n]},idn==Reverse[idn]]; Total[ IntegerDigits[ #]]&/@ Select[Prime[Range[5000]],palQ] (* _Harvey P. Dale_, Oct 10 2014 *)
%Y Cf. A002385, A007953, A007605.
%K nonn,base,less
%O 1,1
%A _Shyam Sunder Gupta_, Oct 11 2013
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