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%I #8 Jan 13 2024 10:52:36
%S 1,2,1,3,4,2,1,4,2,1,2,1,2,1,4,2,1,6,3,12,6,3,4,2,1,4,2,1,2,1,2,1,4,2,
%T 1,9,6,3,6,3,4,2,1,6,3,8,4,2,1,6,3,12,6,3,8,4,2,1,2,1,2,1,6,3,8,4,2,1,
%U 4,2,1,12,6,3,9,18,9,16,8,4,2,1,2,1,4,2,1,8,4,2,1,6,3,8,4,2,1,6,3,18
%N a(1)=1, and for n>1, a(n) = a(n-1)/2, if a(n-1) is divisible by 2, otherwise a(n) = A000005(n*a(n-1)).
%C The formula could be generalized to a class of sequences as a(n)= A000005(A*a(n-1)+B) if a(n-1) is not divisible by C, else a(n)= a(n-1)/C, where A, B, C are integers. In this case we have A=n, B=0 and C=2.
%o (MIT/GNU Scheme) (define (A133923 n) (cond ((< n 2) n) ((even? (A133923 (-1+ n))) (/ (A133923 (-1+ n)) 2)) (else (A000005 (* n (A133923 (-1+ n)))))))
%Y Cf. A000005.
%K nonn
%O 1,2
%A _Ctibor O. Zizka_, Jan 07 2008
%E Edited, corrected, extended and Scheme-code added by _Antti Karttunen_, Oct 05 2009