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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.

A324885 a(1) = 0; for n > 1, a(n) = A001511(A323243(n)).

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%I A324885 #9 Mar 28 2019 20:23:39
%S A324885 0,1,1,3,1,2,1,4,3,1,1,3,1,2,2,4,1,2,1,3,1,5,1,4,3,3,4,5,1,6,1,6,2,5,
%T A324885 2,4,1,2,5,4,1,2,1,3,3,6,1,5,3,1,3,3,1,2,1,4,5,2,1,3,1,5,3,4,2,6,1,5,
%U A324885 2,2,1,4,1,3,2,5,2,6,1,5,4,5,1,3,5,4,6,5,1,2,1,6,2,5,3,4,1,1,5,4,1,2,1,4,6
%N A324885 a(1) = 0; for n > 1, a(n) = A001511(A323243(n)).
%H A324885 Antti Karttunen, <a href="/A324885/b324885.txt">Table of n, a(n) for n = 1..10000</a> (based on Hans Havermann's factorization of A156552)
%H A324885 <a href="/index/Pri#prime_indices">Index entries for sequences computed from indices in prime factorization</a>
%H A324885 <a href="/index/Si#SIGMAN">Index entries for sequences related to sigma(n)</a>
%F A324885 a(1) = 0; for n > 1, a(n) = A001511(A323243(n)).
%F A324885 For n > 1, a(n) = A286357(A156552(n)).
%o A324885 (PARI)
%o A324885 A001511ext(n) = if(!n,n,sign(n)*(1+valuation(n,2))); \\ Like A001511 but gives 0 for 0 and -A001511(-n) for negative numbers.
%o A324885 A324885(n) = A001511ext(A323243(n)); \\ Needs also code from A323243.
%Y A324885 Cf. A001511, A156552, A286357, A323243, A324725, A324813 (positions of terms <= 1), A324817, A324823, A324883.
%K A324885 nonn
%O A324885 1,4
%A A324885 _Antti Karttunen_, Mar 28 2019