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 A340197 #15 Jan 06 2021 09:07:19
%S A340197 1,0,0,2,0,7,0,6,6,13,0,13,0,19,22,18,0,19,0,23,32,31,0,53,20,37,24,
%T A340197 33,0,21,0,54,52,49,58,110,0,55,62,95,0,29,0,53,52,67,0,185,42,53,82,
%U A340197 63,0,139,94,137,92,85,0,321,0,91,74,162,112,45,0,83,112,45,0,403,0,109,82,93,136,53,0,331,114,121
%N A340197 a(1) = 1; for n > 1, a(n) = Sum_{d|n, d<n} (A318833(n/d)-1) * A340197(d).
%C A340197 See comments and question in A340140.
%H A340197 Antti Karttunen, <a href="/A340197/b340197.txt">Table of n, a(n) for n = 1..16384</a>
%F A340197 a(1) = 1; for n > 1, a(n) = Sum_{d|n, d<n} (A318833(n/d)-1) * A340197(d).
%o A340197 (PARI)
%o A340197 A023900(n) = factorback(apply(p -> 1-p, factor(n)[, 1]));
%o A340197 A318833(n) = (n+A023900(n));
%o A340197 A340197(n) = if(1==n,1,sumdiv(n,d,if(d<n,(A318833(n/d)-1)*A340197(d),0)));
%Y A340197 Cf. A023900, A318833, A340140, A340367.
%K A340197 nonn
%O A340197 1,4
%A A340197 _Antti Karttunen_, Jan 05 2021