A079420 Duplicate of A076895.
0, 1, 2, 3, 3, 4, 4, 5, 6, 7, 7, 8, 9, 10, 10, 11, 11, 12, 12, 13, 14, 15, 15, 16, 16, 17, 17, 18
Offset: 1
This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.
[n eq 1 select 1 else n-Self(Self(Ceiling(n/2))): n in [1..80]]; // Vincenzo Librandi, Oct 25 2017
f:= proc(n) option remember; n - procname(procname(ceil(n/2))) end proc: f(1):= 1: seq(f(n),n=1..100); # Robert Israel, Oct 24 2017
Fold[Append[#1, #2 - #1[[#1[[Ceiling[#2/2] ]] ]] ] &, {1}, Range[2, 74]] (* Michael De Vlieger, Oct 24 2017 *)
a(n)=if(n<2,1,n-a(a(ceil(n/2))))