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a(n) = floor(n*r)-a(n-1), where r is the golden mean, (1+sqrt(5))/2.
4

%I #19 May 12 2024 15:25:01

%S 0,1,2,2,4,4,5,6,6,8,8,9,10,11,11,13,12,15,14,16,16,17,18,19,19,21,21,

%T 22,23,23,25,25,26,27,28,28,30,29,32,31,33,33,34,35,36,36,38,38,39,40,

%U 40,42,42,43,44,44,46,46,47,48,49,49,51,50,53,52,54,54,56,55,58,56,60,58

%N a(n) = floor(n*r)-a(n-1), where r is the golden mean, (1+sqrt(5))/2.

%C a(2n+2) - a(2n) = A339824(n), since a(2n+2) - a(2n) = a(2n+2) + a(2n+1) - a(2n+1) - a(2n) = floor((2n+2)r) - floor((2n+1)r). - _Michel Dekking_, Feb 23 2021

%H Paolo Xausa, <a href="/A129229/b129229.txt">Table of n, a(n) for n = 0..10000</a>

%F a(n) = floor(n*r)-floor((n-1)*r)+floor((n-2)*r)-...+d*floor(r), where d=(-1)^(n+1) and r = (1+sqrt(5))/2.

%F a(n) + a(n-1) = floor(n*r). - _Michel Dekking_, Feb 23 2021

%t nxt[{n_,a_}]:={n+1,Floor[GoldenRatio(n+1)]-a}; Transpose[NestList[nxt,{0,0},80]][[2]] (* _Harvey P. Dale_, Dec 08 2015 *)

%t Block[{n = 0}, NestList[Floor[++n*GoldenRatio] - # &, 0, 100]] (* _Paolo Xausa_, May 12 2024 *)

%Y Cf. A001622, A129230, A129231, A087851, A339824, A339825.

%K nonn

%O 0,3

%A _Clark Kimberling_, Apr 04 2007