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 A364257 #10 Jul 17 2023 17:12:33
%S A364257 1,-2,-3,0,-1,6,-1,0,0,2,-1,0,-1,2,5,0,-1,0,-1,0,3,2,-1,0,-4,2,26,0,
%T A364257 -1,-10,-1,0,3,2,-3,0,-1,2,5,0,-1,-6,-1,0,-6,2,-1,0,0,8,5,0,-1,-52,-9,
%U A364257 0,3,2,-1,0,-1,2,8,0,1,-6,-1,0,3,6,-1,0,-1,2,18,0,-5,-10,-1,0,-102,2,-1,0,-3,2,5,0,-1,12
%N A364257 Dirichlet inverse of A364255.
%H A364257 Antti Karttunen, <a href="/A364257/b364257.txt">Table of n, a(n) for n = 1..20000</a>
%H A364257 <a href="/index/Bi#binary">Index entries for sequences related to binary expansion of n</a>
%F A364257 a(1) = 1, and for n > 1, a(n) = -Sum_{d|n, d<n} A364255(n/d) * a(d).
%o A364257 (PARI)
%o A364257 \\ Needs also code from A364255:
%o A364257 memoA364257 = Map();
%o A364257 A364257(n) = if(1==n,1,my(v); if(mapisdefined(memoA364257,n,&v), v, v = -sumdiv(n,d,if(d<n,A364255(n/d)*A364257(d),0)); mapput(memoA364257,n,v); (v)));
%Y A364257 Cf. A163511, A364255.
%Y A364257 Cf. A323239 (read modulo 2).
%K A364257 sign
%O A364257 1,2
%A A364257 _Antti Karttunen_, Jul 17 2023