%I #17 Sep 08 2022 08:45:08
%S 1,1,2,3,4,5,5,6,6,7,7,8,9,10,10,11,12,13,14,15,16,17,17,18,19,20,20,
%T 21,22,23,24,25,25,26,26,27,27,28,29,30,30,31,31,32,33,34,34,35,35,36,
%U 36,37,38,39,39,40,40,41,42,43,43,44,44,45,46,47,47,48,49,50,51,52,53,54
%N a(1)=1, a(n) = n - a(a(ceiling(n/2))).
%H Robert Israel, <a href="/A079411/b079411.txt">Table of n, a(n) for n = 1..10000</a>
%F a(n) is asymptotic to n*(sqrt(3)-1); conjecture: (a(n)-n*(sqrt(3)-1))/log(n) is bounded.
%p f:= proc(n) option remember;
%p n - procname(procname(ceil(n/2)))
%p end proc:
%p f(1):= 1:
%p seq(f(n),n=1..100); # _Robert Israel_, Oct 24 2017
%t Fold[Append[#1, #2 - #1[[#1[[Ceiling[#2/2] ]] ]] ] &, {1}, Range[2, 74]] (* _Michael De Vlieger_, Oct 24 2017 *)
%o (PARI) a(n)=if(n<2,1,n-a(a(ceil(n/2))))
%o (Magma) [n eq 1 select 1 else n-Self(Self(Ceiling(n/2))): n in [1..80]]; // _Vincenzo Librandi_, Oct 25 2017
%Y Cf. A076895.
%K nonn
%O 1,3
%A _Benoit Cloitre_, Feb 16 2003