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A173564 a(n) = a(n-1) + a(n-2) - [a(n-3)/4] - [a(n-4)/2] - [a(n-5)/4]. 1

%I #13 May 18 2021 12:01:11

%S 1,1,2,3,5,8,12,18,26,36,50,68,92,124,165,220,291,385,508,670,882,

%T 1161,1526,2005,2633,3457,4536,5952,7807,10239,13426,17604,23080,

%U 30258,39665,51995,68155,89335,117096,153480,201168,263669,345586,452949,593664,778091,1019808,1336613,1751830,2296030,3009281

%N a(n) = a(n-1) + a(n-2) - [a(n-3)/4] - [a(n-4)/2] - [a(n-5)/4].

%C The limiting ratio a(n+1)/a(n) at the 500th iteration is:1.3106397635502627

%F a(n)=a(n-1)+a(n-2)-Floor[a(n-3)/4]-Floor[a(n-4)/2]-Floor[a(n-5)/4]

%t f[-3] = 0; f[-2] = 0; f[-1] = 0; f[0] = 1; f[1] = 1;

%t f[n_] := f[n] = f[n - 1] + f[n - 2] - Floor[f[n - 3]/

%t 4] - Floor[f[n - 4]/2] - Floor[f[n - 5]/4]

%t Table[f[n], {n, 0, 50}]

%t RecurrenceTable[{a[0]==a[1]==1,a[2]==2,a[3]==3,a[4]==5,a[n]== a[n-1]+ a[n-2]- Floor[a[n-3]/4]-Floor[a[n-4]/2]-Floor[a[n-5]/4]},a,{n,50}] (* _Harvey P. Dale_, May 18 2021 *)

%Y Cf. A173538

%K nonn

%O 0,3

%A _Roger L. Bagula_, Nov 23 2010

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Last modified April 18 22:18 EDT 2024. Contains 371782 sequences. (Running on oeis4.)