# Greetings from The On-Line Encyclopedia of Integer Sequences! http://oeis.org/ Search: id:a324117 Showing 1-1 of 1 %I A324117 #7 Feb 20 2019 21:43:15 %S A324117 0,1,1,2,1,2,1,2,2,3,1,2,1,2,2,4,1,2,1,2,3,4,1,2,2,4,2,4,1,4,1,2,2,4, %T A324117 2,4,1,2,4,4,1,2,1,2,2,8,1,2,2,3,4,2,1,2,3,2,4,6,1,2,1,4,2,6,2,4,1,4, %U A324117 2,2,1,4,1,4,2,4,2,4,1,2,4,4,1,6,4,8,8,8,1,6,3,4,6,12,4,4,1,3,4,4,1,6,1,2,4 %N A324117 Number of odd divisors in A156552(n): a(1) = 0, for n > 1, a(n) = A001227(A156552(n)) = A000005(A322993(n)). %H A324117 Antti Karttunen, Table of n, a(n) for n = 1..4473 %H A324117 Index entries for sequences computed from indices in prime factorization %F A324117 a(1) = 0; for n > 1, a(n) = A000005(A322993(n)) = A000005(A156552(2*A246277(n))) = A324105(2*A246277(n)). %o A324117 (PARI) 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 A324117 A156552(n) = if(1==n, 0, if(!(n%2), 1+(2*A156552(n/2)), 2*A156552(A064989(n)))); %o A324117 A246277(n) = { if(1==n, 0, while((n%2), n = A064989(n)); (n/2)); }; %o A324117 A322993(n) = A156552(2*A246277(n)); %o A324117 A324117(n) = if(1==n, 0, numdiv(A322993(n))); %Y A324117 Cf. A000005, A001227, A156552, A246277, A322813, A322993, A324105, A324115, A324118. %K A324117 nonn %O A324117 1,4 %A A324117 _Antti Karttunen_, Feb 20 2019 # Content is available under The OEIS End-User License Agreement: http://oeis.org/LICENSE