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A173633
a(n) = a(n-2) + a(n-3) - [a(n-3)/4] - [a(n-4)/2] - [a(n-5)/4].
0
1, 1, 1, 2, 2, 3, 4, 4, 6, 6, 7, 8, 8, 10, 10, 11, 12, 12, 14, 14, 15, 16, 16, 18, 18, 19, 20, 20, 22, 22, 23, 24, 24, 26, 26, 27, 28, 28, 30, 30, 31, 32, 32, 34, 34, 35, 36, 36, 38, 38, 39
OFFSET
0,4
COMMENTS
The limiting ratio a(n+1)/a(n) goes very near one in two alternating modes.
FORMULA
a(n)=a(n-2)+a(n-3)-Floor[a(n-3)/4]-Floor[a(n-4)/2]-Floor[a(n-5)/4]
MATHEMATICA
f[-3] = 0; f[-2] = 0; f[-1] = 0; f[0] = 1; f[1] = 1;
f[n_] := f[n] = f[n - 2] + f[n - 3] - Floor[f[n - 3]/
4] - Floor[f[n - 4]/2] - Floor[f[n - 5]/4]
Table[f[n], {n, 0, 50}]
CROSSREFS
Sequence in context: A211317 A126246 A338517 * A138369 A173332 A348526
KEYWORD
nonn
AUTHOR
Roger L. Bagula, Nov 23 2010
STATUS
approved