%I #12 Nov 12 2019 11:13:46
%S 1,1,3,4,8,13,27,56,112,169,367,748,1501,3006,6013,12028,24056,36085,
%T 78185,159377,320259,641271,1282923,2566044,5132145,10264346,20528721,
%U 41057456,82114917,164229838,328459677,656919356,1313838712
%N a(n) = a(1) + a(2) + ... + a(n-1) - a(m) for n >= 4, where m = 2^(p+1) + 2 - n and p is the unique integer such that 2^p < n - 1 <= 2^(p+1), starting with a(1) = a(2) = 1 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;
%p `if`(n < 4, [1,1,3][n], s(n - 1) - a(2^ceil(log[2](n - 1)) + 2 - n)):
%p end proc:
%p seq(a(n), n = 1..34); # _Petros Hadjicostas_, Nov 11 2019
%Y Cf. A049885.
%K nonn
%O 1,3
%A _Clark Kimberling_
%E Name edited by _Petros Hadjicostas_, Nov 11 2019
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