cp's OEIS Frontend

A049979 a(n) = a(1) + a(2) + ... + a(n-1) + a(m) for n >= 4, where m = 2*n - 2 - 2^(p+1) and p is the unique integer such that 2^p < n-1 <= 2^(p+1), with a(1) = 1, a(2) = 3, and a(3) = 4.

%I A049979 #17 Sep 26 2019 01:54:24
%S A049979 1,3,4,11,30,52,112,265,743,1224,2456,4953,10119,21197,46123,108490,
%T A049979 304273,500059,1000126,2000293,4000799,8002557,16008843,32033930,
%U A049979 64155153,128701875,258903984,523810232,1071651837,2239971619
%N A049979 a(n) = a(1) + a(2) + ... + a(n-1) + a(m) for n >= 4, where m = 2*n - 2 - 2^(p+1) and p is the unique integer such that 2^p < n-1 <= 2^(p+1), with a(1) = 1, a(2) = 3, and a(3) = 4.
%F A049979 a(n) = a(1 + A006257(n-2)) + Sum_{i = 1..n-1} a(i) for n >= 4 with a(1) = 1, a(2) = 3, and a(3) = 4. - _Petros Hadjicostas_, Sep 24 2019
%e A049979 From _Petros Hadjicostas_, Sep 24 2019: (Start)
%e A049979 a(4) = a(1 + A006257(4-2)) + a(1) + a(2) + a(3) = a(2) + a(1) + a(2) + a(3) = 3 + 1 + 3 + 4 = 11.
%e A049979 a(7) = a(1 + A006257(7-2)) + a(1) + ... + a(6) = a(4) + a(1) + ... + a(6) = 11 + 1 + 3 + 4 + 11 + 30 + 52 = 112.
%e A049979 (End)
%p A049979 a := proc(n) local i; option remember; if n < 4 then return [1, 3, 4][n]; end if; add(a(i), i = 1 .. n - 1) + a(2*n - 3 - Bits:-Iff(n - 2, n - 2)); end proc;
%p A049979 seq(a(n), n = 1 .. 37); # _Petros Hadjicostas_, Sep 24 2019, courtesy of _Peter Luschny_
%Y A049979 Cf. A006257, A049939, A049940, A049960, A049964.
%K A049979 nonn
%O A049979 1,2
%A A049979 _Clark Kimberling_
%E A049979 Name edited by _Petros Hadjicostas_, Sep 24 2019