This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.
%I A104261 #9 Jul 30 2015 22:33:03
%S A104261 2,0,0,0,0,0,0,0,2,2,0,0,4,4,4,0,0,6,6,0,0,0,8,8,0,0,0,0,0,0,2,0,0,0,
%T A104261 4,0,0,6,6,0,0,8,0,0,0,0,2,4,4,4,2,2,6,2,2,8,8,2,2,10,10,2,0,0,0,0,0,
%U A104261 0,4,4,0,0,6,0,0,8,8,0,4,4,4,6,4,4,4,8,8,4,10,10,10,4,12,4,4,0,0,2,2,4,4,0
%N A104261 Sum of even digits (0,2,4,6,8) of n-th prime.
%F A104261 A104261(n) = A007605(n) - A104260(n).
%t A104261 sodev={};Do[id=IntegerDigits[Prime[i]];lid=Length[id];sod=Sum[If[EvenQ[id[[k]]], id[[k]], 0], {k, lid}];sodev={sodev, sod}, {i, 200}];sodev//Flatten
%t A104261 f[n_] := Plus @@ Select[ IntegerDigits[ Prime[n]], EvenQ[ # ] && # > 1 &]; Table[ f[n], {n, 102}] (* _Robert G. Wilson v_, Nov 03 2005 *)
%Y A104261 Sum of odd digits (1, 3, 5, 7, 9) of n-th prime: A104260, sum of prime digits (2, 3, 5, 7) of n-th prime: A104250, sum of composite (nonprime) digits (1, 4, 6, 8, 9) of n-th prime: A104251, sum of digits of primes: A007605, primes: A000040.
%K A104261 nonn,base
%O A104261 1,1
%A A104261 _Zak Seidov_, Feb 26 2005