OFFSET
0,4
COMMENTS
This sequence is interesting because in the graph of a(n+1)/a(n) there are four modes all approaching one at different rates.
LINKS
Bo Gyu Jeong, Table of n, a(n) for n = 0..2010
Index entries for linear recurrences with constant coefficients, signature (1,0,0,0,0,0,0,0,1,-1).
FORMULA
a(n+30) = a(n)+30 for n>=12.
From Chai Wah Wu, Apr 14 2024: (Start)
a(n) = a(n-1) + a(n-2) - a(n-4) - a(n-6) + a(n-8) + a(n-9) - a(n-10) for n > 21.
G.f.: (x^21 - x^20 + x^18 - x^16 + x^14 - x^13 + x^11 - x^9 + x^7 - x^2 + 1)/(x^10 - x^9 - x^8 + x^6 + x^4 - x^2 - x + 1). (End)
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 - 2] + f[n - 3] - Floor[f[n - 3]/2] - Floor[f[n - 6]/2]
Table[f[n], {n, 0, 50}]
CROSSREFS
KEYWORD
nonn
AUTHOR
Roger L. Bagula, Nov 22 2010
EXTENSIONS
More terms from Bo Gyu Jeong, Jun 15 2012
STATUS
approved