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A229137
a(1) = a(2) = 1; if n == 0 (mod 3), then a(n) = a(n/3), otherwise a(n) = a(n-1) + a(n-2).
2
1, 1, 1, 2, 3, 1, 4, 5, 1, 6, 7, 2, 9, 11, 3, 14, 17, 1, 18, 19, 4, 23, 27, 5, 32, 37, 1, 38, 39, 6, 45, 51, 7, 58, 65, 2, 67, 69, 9, 78, 87, 11, 98, 109, 3, 112, 115, 14, 129, 143, 17, 160, 177, 1, 178, 179, 18, 197, 215, 19, 234, 253, 4, 257, 261, 23, 284
OFFSET
1,4
COMMENTS
A distant cousin of Fibonacci numbers. - T. D. Noe, Sep 23 2013
MATHEMATICA
f[1] = f[2] = 1; f[n_] := f[n] = If[Mod[n, 3] == 0, f[n/3], (f[n - 1] + f[n - 2])]; Table[f[n], {n, 100}]
CROSSREFS
Cf. A030067.
Sequence in context: A038802 A092942 A376930 * A358631 A358106 A282510
KEYWORD
nonn
AUTHOR
STATUS
approved