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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.

A348045 Möbius transform of A252463, where A252463 shifts the prime factorization of odd numbers one step towards smaller primes and divides even numbers by two.

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%I A348045 #14 Oct 14 2021 19:16:33
%S A348045 1,0,1,1,2,1,4,2,2,2,6,2,10,2,2,4,12,4,16,4,4,4,18,4,6,2,4,6,22,6,28,
%T A348045 8,6,4,8,6,30,2,10,8,36,8,40,10,4,4,42,8,20,14,12,12,46,14,12,12,16,6,
%U A348045 52,8,58,2,8,16,20,14,60,16,18,16,66,12,70,6,6,18,24,14,72,16,8,4,78,12,24,2,22,20,82,20
%N A348045 Möbius transform of A252463, where A252463 shifts the prime factorization of odd numbers one step towards smaller primes and divides even numbers by two.
%H A348045 Antti Karttunen, <a href="/A348045/b348045.txt">Table of n, a(n) for n = 1..16384</a>
%H A348045 <a href="/index/Pri#prime_indices">Index entries for sequences computed from indices in prime factorization</a>
%F A348045 a(n) = Sum_{d|n} A008683(n/d) * A252463(d).
%o A348045 (PARI)
%o A348045 A064989(n) = {my(f); f = factor(n); if((n>1 && f[1,1]==2), f[1,2] = 0); for (i=1, #f~, f[i,1] = precprime(f[i,1]-1)); factorback(f)};
%o A348045 A252463(n) = if(!(n%2),n/2,A064989(n));
%o A348045 A348045(n) = sumdiv(n,d,moebius(n/d)*A252463(d));
%Y A348045 Cf. A008683, A064989, A252463, A285702 (odd bisection), A348046 (positions of 2's).
%Y A348045 Cf. also A023022, A326305, A347115.
%K A348045 nonn,look
%O A348045 1,5
%A A348045 _Antti Karttunen_, Oct 12 2021