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 A035260 #7 Jul 30 2020 12:19:08 %S A035260 1,3,4,5,7,9,12,15,16,17,20,21,25,27,28,35,36,37,41,43,45,47,48,49,51, %T A035260 59,60,63,64,67,68,75,79,80,81,83,84,85,89,100,101,105,108,109,111, %U A035260 112,119,121,123,125,127,129,131,135,140,141,144,147,148,151,153 %N A035260 Indices of the nonzero terms in expansion of Dirichlet series Product_p (1-(Kronecker(m,p)+1)*p^(-s)+Kronecker(m,p)*p^(-2s))^(-1) for m= 21. %o A035260 (PARI) m=21; select(x -> x, direuler(p=2,101,1/(1-(kronecker(m,p)*(X-X^2))-X)), 1) %Y A035260 Cf. A035203 (the expansion itself). %K A035260 nonn %O A035260 1,2 %A A035260 _N. J. A. Sloane_ %E A035260 Edited and extended by _Andrey Zabolotskiy_, Jul 30 2020