login
The OEIS is supported by the many generous donors to the OEIS Foundation.

 

Logo
Hints
(Greetings from The On-Line Encyclopedia of Integer Sequences!)
A050064 a(n) = 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 and a(2) = a(3) = 3. 10

%I #18 Nov 19 2019 05:51:20

%S 1,3,3,4,7,8,11,18,29,30,33,40,51,80,113,164,277,278,281,288,299,328,

%T 361,412,525,802,1083,1382,1743,2268,3351,5094,8445,8446,8449,8456,

%U 8467,8496,8529,8580,8693,8970,9251,9550,9911,10436

%N a(n) = 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 and a(2) = a(3) = 3.

%C Variant of A050032 or A050048. - _R. J. Mathar_, Oct 15 2008

%H Ivan Neretin, <a href="/A050064/b050064.txt">Table of n, a(n) for n = 1..8193</a>

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

%p `if`(n < 4, [1, 3, 3][n], a(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 18 2019

%t Fold[Append[#1, #1[[-1]] + #1[[#2]]] &, {1, 3, 3}, Flatten@Table[2 k - 1, {n, 5}, {k, 2^n}]] (* _Ivan Neretin_, Sep 07 2015 *)

%Y Cf. similar sequences with different initial conditions: A050024 (1,1,1), A050028 (1,1,2), A050032 (1,1,3), A050036 (1,1,4), A050040 (1,2,1), A050044 (1,2,2), A050048 (1,2,3), A050052 (1,2,4), A050056 (1,3,1), A050060 (1,3,2), A050068 (1,3,4).

%K nonn

%O 1,2

%A _Clark Kimberling_

%E Name edited by _Petros Hadjicostas_, Nov 18 2019

Lookup | Welcome | Wiki | Register | Music | Plot 2 | Demos | Index | Browse | More | WebCam
Contribute new seq. or comment | Format | Style Sheet | Transforms | Superseeker | Recents
The OEIS Community | Maintained by The OEIS Foundation Inc.

License Agreements, Terms of Use, Privacy Policy. .

Last modified April 20 07:43 EDT 2024. Contains 371799 sequences. (Running on oeis4.)