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A074934
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Number of integers in {1, 2, ..., Fibonacci(n)} that are coprime to n.
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0
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1, 1, 2, 2, 4, 3, 12, 11, 23, 22, 81, 48, 216, 162, 325, 494, 1504, 861, 3961, 2706, 6256, 8051, 27412, 15456, 60020, 56028, 130946, 136205, 496497, 221878, 1302841, 1089155, 2136108, 2683712, 6327404, 4976784, 23504904, 18515449, 38920607, 40933662, 161541601
(list; graph; refs; listen; history; internal format)
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OFFSET
| 1,3
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COMMENTS
| Compare the definition of a(n) to phi(n) = number of integers in {1, 2, ..., n} that are coprime to n.
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EXAMPLE
| There are four integers in {1, 2, ..., Fibonacci(5) = 5} that are coprime to 5, i.e. 1, 2, 3, 4. Hence a(5) = 4.
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MATHEMATICA
| h[n_] := Module[{l}, l = {}; For[i = 1, i <= Fibonacci[n], i++, If[GCD[i, n] == 1, l = Append[l, i]]]; l]; Table[Length[h[i]], {i, 1, 21}]
Table[Count[Range[Fibonacci[n]], _?(CoprimeQ[#, n]&)], {n, 25}] (* From Harvey P. Dale, Oct 31 2011 *)
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CROSSREFS
| Sequence in context: A140860 A019681 A054529 * A089886 A071511 A119922
Adjacent sequences: A074931 A074932 A074933 * A074935 A074936 A074937
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KEYWORD
| nonn
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AUTHOR
| Joseph L. Pe (joseph_l_pe(AT)hotmail.com), Oct 04 2002
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EXTENSIONS
| More terms from Harvey P. Dale, Oct. 31 2011
a(26)-a(41) from Donovan Johnson (donovan.johnson(AT)yahoo.com), Nov 03 2011
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