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 A104251 #7 Nov 21 2019 04:04:31 %S A104251 0,0,0,0,2,1,1,10,0,9,1,0,5,4,4,0,9,7,6,1,0,9,8,17,9,2,1,1,10,2,1,2,1, %T A104251 10,14,2,1,7,7,1,10,10,11,10,10,19,2,0,0,9,0,9,5,1,0,6,15,1,0,9,8,9,0, %U A104251 2,1,1,1,0,4,13,0,9,6,0,9,8,17,9,5,13,14,5,5,4,13,8,17,4,11,10,10,13,12 %N A104251 Sum of nonprime digits of n-th prime. %F A104251 a(n) = A007605(n) - A104250(n). %e A104251 a(6)=1 because sum of composite (nonprime) digits of prime(6)=13 is 1. %Y A104251 Cf. A000040 (primes). %Y A104251 Cf. A007605 (sum of digits of primes), A104250 (sum of prime digits of n-th prime). %K A104251 nonn,base %O A104251 1,5 %A A104251 _Zak Seidov_, Feb 26 2005