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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) = 3, and a(3) = 2.
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%I #11 Nov 16 2019 03:28:47

%S 1,3,2,7,15,29,59,131,306,554,1109,2231,4506,9259,19321,42039,98893,

%T 178466,356933,713879,1427802,2855851,5712505,11428407,22871629,

%U 45822830,91903700,184878269,374041241,765241606,1599515283

%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) = 3, and a(3) = 2.

%p s := proc(n) option remember; `if`(n < 1, 0, a(n) + s(n - 1)) end proc:

%p a := proc(n) option remember;

%p `if`(n < 4, [1, 3, 2][n], 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