A049958 a(n) = a(1) + a(2) + ... + a(n-1) + a(m) for n >= 4, where m = n - 1 - 2^p 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.

1, 2, 3, 7, 15, 29, 59, 119, 242, 478, 957, 1915, 3834, 7676, 15366, 30762, 61584, 123050, 246101, 492203, 984410, 1968828, 3937670, 7875370, 15750800, 31501723, 63003682, 126007843, 252016644, 504035207, 1008074256, 2016156202

Offset

1,2

Links

Table of n, a(n) for n=1..32.

Maple

s := proc(n) option remember; `if`(n < 1, 0, a(n) + s(n - 1)); end proc;
a := proc(n) option remember; `if`(n < 4, [1, 2, 3][n], s(n - 1) + a(-2^ceil(log[2](n - 1) - 1) + n - 1)); end proc;
seq(a(n), n = 1 .. 40); # Petros Hadjicostas, Apr 23 2020

Crossrefs

Cf. A049910 (similar, but with minus a(m)), A049911 (similar, but with minus a(2*m)), A049959 (similar, but with plus a(2*m)).

Sequence in context: A006884 A074742 A020873 * A298403 A177487 A153010

Adjacent sequences: A049955 A049956 A049957 * A049959 A049960 A049961

Keyword

nonn

Author

Clark Kimberling

Extensions

Name edited by Petros Hadjicostas, Apr 23 2020

Status

approved