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%I #8 Dec 01 2017 18:51:07
%S 0,0,0,1,1,1,2,2,1,2,3,3,6,4,6,4,2,3,5,5,8,7,11,6,12,12,18,9,31,13,20,
%T 8,3,5,8,7,13,10,15,10,19,17,26,15,43,22,33,12,30,24,36,25,61,37,56,
%U 18,85,62,93,27,156,40,60,16,4,6,9,11,16,16,24,14,22,27,41,21,68,31,47,20,35,38,57,35,96,52,78
%N a(n) = floor(A005940(1+n)/4).
%H Antti Karttunen, <a href="/A292602/b292602.txt">Table of n, a(n) for n = 0..16383</a>
%H <a href="/index/Pri#prime_indices">Index entries for sequences computed from indices in prime factorization</a>
%F a(n) = A002265(A005940(1+n)).
%F 4*a(n) + A292603(n) = A005940(1+n).
%e The first six levels of the binary tree (compare also to the illustrations given at A005940 and A292603):
%e 0
%e |
%e ...................0...................
%e 0 1
%e 1......../ \........1 2......../ \........2
%e / \ / \ / \ / \
%e / \ / \ / \ / \
%e / \ / \ / \ / \
%e 1 2 3 3 6 4 6 4
%e 2 3 5 5 8 7 11 6 12 12 18 9 31 13 20 8
%o (Scheme) (define (A292602 n) (let* ((x (A005940 (+ 1 n))) (d (modulo x 4))) (/ (- x d) 4)))
%Y Cf. A002265, A003961, A005940, A292603, A295895.
%K nonn
%O 0,7
%A _Antti Karttunen_, Dec 01 2017