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A324391 Fully multiplicative with a(p^e) = A070939(p)^e, where A070939(p) gives the length of the binary representation of p.

%I A324391 #8 Mar 05 2019 18:19:06
%S A324391 1,2,2,4,3,4,3,8,4,6,4,8,4,6,6,16,5,8,5,12,6,8,5,16,9,8,8,12,5,12,5,
%T A324391 32,8,10,9,16,6,10,8,24,6,12,6,16,12,10,6,32,9,18,10,16,6,16,12,24,10,
%U A324391 10,6,24,6,10,12,64,12,16,7,20,10,18,7,32,7,12,18,20,12,16,7,48,16,12,7,24,15,12,10,32,7,24,12,20,10,12
%N A324391 Fully multiplicative with a(p^e) = A070939(p)^e, where A070939(p) gives the length of the binary representation of p.
%H A324391 Antti Karttunen, <a href="/A324391/b324391.txt">Table of n, a(n) for n = 1..65537</a>
%F A324391 For all n >= 1, a(A000668(n)) = A000043(n).
%o A324391 (PARI)
%o A324391 A070939(n) = if(!n,1,#binary(n));
%o A324391 A324391(n) = { my(f = factor(n)); for (i=1, #f~, f[i, 1] = A070939(f[i, 1])); factorback(f); };
%Y A324391 Cf. A000043, A000668, A070939, A072084.
%K A324391 nonn,mult
%O A324391 1,2
%A A324391 _Antti Karttunen_, Mar 05 2019