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A129896
a(1)=1. a(n) = a(n-1) + number of Fibonacci numbers among the first (n-1) terms of the sequence.
1
1, 2, 4, 6, 8, 11, 14, 17, 20, 23, 26, 29, 32, 35, 38, 41, 44, 47, 50, 53, 56, 59, 62, 65, 68, 71, 74, 77, 80, 83, 86, 89, 93, 97, 101, 105, 109, 113, 117, 121, 125, 129, 133, 137, 141, 145, 149, 153, 157, 161, 165, 169, 173, 177, 181, 185, 189, 193, 197, 201, 205, 209
OFFSET
1,2
COMMENTS
The Fibonacci numbers in this sequence are: 1, 2, 8, 89, 233, 46368, 14930352, ..., . (A131349) - Robert G. Wilson v, Jul 02 2007
MATHEMATICA
fibQ[n_] := (Fibonacci@ Round@ Log[ GoldenRatio, n*Sqrt@5] == n); f[lst_] := Append[lst, Last@lst + Length@Select[lst, fibQ@# &]]; Nest[f, {1}, 38] (* Robert G. Wilson v, Jul 02 2007 *)
nxt[{fibs_, a_}]:=Module[{f=Fibonacci[Range[50]], x=fibs}, If[MemberQ[f, a], x++]; {x, a+x}]; NestList[nxt, {0, 1}, 70][[All, 2]] (* Harvey P. Dale, Sep 16 2020 *)
CROSSREFS
Sequence in context: A331417 A077473 A200738 * A134421 A092777 A186380
KEYWORD
nonn
AUTHOR
Leroy Quet, Jun 04 2007
EXTENSIONS
More terms from Robert G. Wilson v, Jul 02 2007
STATUS
approved