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 A378436 #11 Nov 26 2024 20:59:30 %S A378436 1,2,2,3,2,5,2,4,3,4,2,9,2,4,4,5,2,9,2,7,4,4,2,16,3,4,4,7,2,12,2,6,4, %T A378436 4,4,21,2,4,4,12,2,11,2,6,6,4,2,28,3,6,4,6,2,14,4,11,4,4,2,53,2,4,6,7, %U A378436 4,11,2,6,4,8,2,60,2,4,6,6,4,10,2,20,5,4,2,43,4,4,4,9,2,41,4,6,4,4,4,51,2,6,6,12 %N A378436 Inverse Möbius transform of A033630, where A033630 is the number of partitions of n into distinct divisors of n. %C A378436 The odd bisection differs from A099774 (the odd bisection of A000005) apparently in the positions given by A005231 (odd abundant numbers): 945, 1575, 2205, 2835, 3465, ... %H A378436 Antti Karttunen, <a href="/A378436/b378436.txt">Table of n, a(n) for n = 1..20000</a> %F A378436 a(n) = Sum_{d|n} A033630(d). %o A378436 (PARI) %o A378436 A033630(n) = if(!n, 1, my(p=1); fordiv(n, d, p *= (1 + 'x^d)); polcoeff(p, n)); %o A378436 A378436(n) = sumdiv(n,d,A033630(d)); %Y A378436 Cf. A000005, A005231, A033630, A099774, A378438 (Dirichlet inverse). %K A378436 nonn %O A378436 1,2 %A A378436 _Antti Karttunen_, Nov 26 2024