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A119249
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Indices of Fibonacci numbers in A081952.
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1
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4, 7, 10, 17, 22, 31, 41, 47, 49, 71, 71, 98, 119, 161, 169, 191, 191, 239, 239, 239, 338, 338, 338, 431, 431, 449
(list; graph; refs; listen; history; internal format)
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OFFSET
| 1,1
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FORMULA
| A081952(n) = F(a(n)), where F(k) is the k-th Fibonacci number.
a(n) = the smallest k>3 such that A086435(A000045(k)-1)>=n. [From Max Alekseyev (maxale(AT)gmail.com), Apr 23 2010]
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EXAMPLE
| A081952(4) = 1597 and 1597 is the 17th Fibonacci number, so a(4) = 17.
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MATHEMATICA
| f[n_, m_, 0] := n == 1; f[n_, m_, d_] := (b = False; l = Select[Divisors[n], #>=m&]; For[i = 1, i <= Length[l], i++, k = l[[i]]; If[f[n / k, k + 1, d - 1], b = True; Break[]]]; b); Do[x = 3; While[ !f[Fibonacci[x] - 1, 2, y], x++ ]; Print[x], {y, 1, 50}]
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CROSSREFS
| Cf. A081952.
Sequence in context: A131500 A003461 A023375 * A071415 A103408 A088408
Adjacent sequences: A119246 A119247 A119248 * A119250 A119251 A119252
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KEYWORD
| hard,more,nonn
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AUTHOR
| Ryan Propper (rpropper(AT)stanford.edu), Jul 22 2006
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EXTENSIONS
| a(24)-a(26) from Max Alekseyev (maxale(AT)gmail.com), Apr 23 2010
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