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 A091398 #14 Oct 17 2022 07:06:07
%S A091398 1,0,0,0,1,0,0,0,0,0,2,0,0,0,0,0,0,0,2,0,0,0,0,0,1,0,0,0,2,0,2,0,0,0,
%T A091398 0,0,0,0,0,0,2,0,0,0,0,0,0,0,0,0,0,0,0,0,2,0,0,0,2,0,2,0,0,0,0,0,0,0,
%U A091398 0,0,2,0,0,0,0,0,0,0,2,0,0,0,0,0,0,0,0,0,2,0,0,0,0,0,2,0,0,0,0,0,2,0,0,0,0
%N A091398 a(n) = Product_{ p | n } (1 + Legendre(5,p) ).
%H A091398 Andrew Howroyd, <a href="/A091398/b091398.txt">Table of n, a(n) for n = 1..1000</a>
%F A091398 Asymptotic mean: Limit_{m->oo} (1/m) * Sum_{k=1..m} a(k) = 5*sqrt(5) * log(phi)/(2*Pi^2) = 0.272559..., where phi is the golden ratio (A001622). - _Amiram Eldar_, Oct 17 2022
%p A091398 with(numtheory); L := proc(n,N) local i,t1,t2; t1 := ifactors(n)[2]; t2 := mul((1+legendre(N,t1[i][1])),i=1..nops(t1)); end; [seq(L(n,5),n=1..120)];
%t A091398 a[n_] := Times @@ (1+KroneckerSymbol[5, #]& /@ FactorInteger[n][[All, 1]]);
%t A091398 Array[a, 105] (* _Jean-François Alcover_, Apr 08 2020 *)
%o A091398 (PARI) a(n)={my(f=factor(n)[,1]); prod(i=1, #f, 1 + kronecker(5, f[i]))} \\ _Andrew Howroyd_, Jul 23 2018
%Y A091398 Cf. A001622, A080891, A091379, A091396.
%K A091398 nonn,mult
%O A091398 1,11
%A A091398 _N. J. A. Sloane_, Mar 02 2004