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%I #17 Nov 16 2019 01:40:34
%S 1,2,3,5,8,18,34,63,100,233,464,923,1820,3574,6784,12212,19460,45703,
%T 91404,182803,365580,731094,1461824,2922292,5839620,11666564,23261184,
%U 46248192,91400140,178422484,339423404,610707852,973392440
%N a(n) = a(1) + a(2) + ... + a(n-1) - a(m) for n >= 4, where m = 2*n - 3 - 2^(p+1) and p is the unique integer such that 2^p < n - 1 <= 2^(p+1), starting with a(1) = 1, a(2) = 2, and a(3) = 3.
%p s := proc(n) option remember; `if`(n < 1, 0, a(n) + s(n - 1)) end proc:
%p a := proc(n) option remember; `if`(n < 4, [1, 2, 3][n],
%p s(n - 1) - a(-2^ceil(log[2](n - 1)) + 2*n - 3))
%p end proc:
%p seq(a(n), n = 1..40); # _Petros Hadjicostas_, Nov 15 2019
%K nonn
%O 1,2
%A _Clark Kimberling_
%E Name edited by _Petros Hadjicostas_, Nov 15 2019
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