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 A346615 #8 Aug 20 2021 18:43:08 %S A346615 1,0,1,2,3,0,5,4,6,0,9,-1,11,0,0,8,15,0,17,-2,-1,0,21,1,20,0,18,-1,27, %T A346615 0,29,16,0,0,5,-1,35,0,-1,7,39,0,41,-1,-2,0,45,-1,42,0,0,-2,51,0,-3, %U A346615 -4,-1,0,57,11,59,0,15,32,10,0,65,-2,0,0,69,-5,71,0,-1,-1,6,0,77,-8 %N A346615 Moebius transform of A344005. %H A346615 N. J. A. Sloane, <a href="/transforms.txt">Transforms</a>. %o A346615 (PARI) f(n) = my(m=1); while ((m*(m+1))%n, m++); m; \\ A344005 %o A346615 a(n) = sumdiv(n, d, moebius(n/d)*f(d)); \\ _Michel Marcus_, Aug 19 2021 %Y A346615 Cf. A011772, A344767, A346614, A344005, A346616. %K A346615 sign %O A346615 0,4 %A A346615 _N. J. A. Sloane_, Aug 18 2021