cp's OEIS Frontend

A049922 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) = 3 and a(3) = 2.

%I A049922 #18 May 06 2022 13:12:15
%S A049922 1,3,2,5,8,18,34,69,135,274,546,1093,2183,4363,8716,17416,34797,69662,
%T A049922 139322,278645,557287,1114571,2229132,4458248,8916461,17832856,
%U A049922 35665573,71330874,142661201,285321312,570640444,1141276535,2282544370
%N A049922 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) = 3 and a(3) = 2.
%o A049922 (PARI) lista(nn) = { my(va = vector(nn)); va[1] = 1; va[2] = 3; va[3] = 2; my(sa = vecsum(va)); for (n=4, nn, va[n] = sa - va[n - 1 - 2^ceil(-1 + log(n-1)/log(2))]; sa += va[n]; ); va; } \\ _Petros Hadjicostas_, Apr 26 2020 (with nn > 2)
%Y A049922 Cf. A049923 (similar, but with minus a(2*m)), A049970 (similar, but with plus a(m)), A049971 (similar, but with plus a(2*m)).
%K A049922 nonn
%O A049922 1,2
%A A049922 _Clark Kimberling_
%E A049922 Name edited by _Petros Hadjicostas_, Apr 26 2020