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Numerator of sum of reciprocals of first n palindromic primes.
2

%I #14 Nov 21 2013 12:47:07

%S 1,5,31,247,2927,297937,39263057,5959285217,1083245729387,

%T 207735268337827,65180687788497661,23058721563350868863,

%U 8618531530355825754989,3307472964561561236731357

%N Numerator of sum of reciprocals of first n palindromic primes.

%H Vincenzo Librandi, <a href="/A046852/b046852.txt">Table of n, a(n) for n = 1..100</a>

%e 1/2 + 1/3 + 1/5 + 1/7 + 1/11 + 1/101 + ... gives 1/2, 5/6, 31/30, 247/210, ...

%t palQ[n_]:=Module[{idn=IntegerDigits[n]},idn==Reverse[idn]]; Numerator[ Accumulate[1/#&/@Select[Prime[Range[200]],palQ]]] (* _Harvey P. Dale_, Dec 21 2011 *)

%Y Cf. A046853, A002385.

%K nonn,frac,base

%O 1,2

%A _G. L. Honaker, Jr._

%E More terms from _Erich Friedman_, Jun 03 2001