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A173597 a(n) = a(n-1) + a(n-2) - [a(n-4)/4] - [a(n-5)/2] - [a(n-6)/4]. 0
1, 1, 2, 3, 5, 8, 13, 20, 31, 47, 70, 104, 154, 227, 334, 489, 716, 1046, 1528, 2229, 3251, 4739, 6906, 10063, 14661, 21358, 31112, 45318, 66008, 96142, 140028, 203946, 297035, 432613, 630068, 917646, 1336476, 1946466, 2834861, 4128729, 6013131, 8757595, 12754659, 18576026, 27054324, 39402205, 57385786, 83577258, 121722786, 177278325, 258189982 (list; graph; refs; listen; history; text; internal format)
OFFSET

0,3

COMMENTS

The limiting ratio a(n+1)/a(n) at the 500th iteration is:1.456410256629193

LINKS

Table of n, a(n) for n=0..50.

FORMULA

a(n)=a(n-1)+a(n-2)-Floor[a(n-4)/4]-Floor[a(n-5)/2]-Floor[a(n-6)/4]

MATHEMATICA

f[-4] = 0; f[-3] = 0; f[-2] = 0; f[-1] = 0; f[0] = 1; f[1] = 1;

f[n_] := f[n] = f[n - 1] + f[n - 2] - Floor[f[n - 4]/4] - Floor[

f[n - 5]/2] - Floor[f[n - 6]/4]

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

CROSSREFS

Sequence in context: A088795 A156145 A216053 * A059923 A266331 A055805

Adjacent sequences:  A173594 A173595 A173596 * A173598 A173599 A173600

KEYWORD

nonn

AUTHOR

Roger L. Bagula, Nov 23 2010

STATUS

approved

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Last modified July 28 00:54 EDT 2021. Contains 346316 sequences. (Running on oeis4.)