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A120255
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Array read by rows, where the n-th row (of A120256(n) terms) lists the positive divisors, not occurring earlier in the array, of the n-th Fibonacci number.
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4
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1, 2, 3, 5, 4, 8, 13, 7, 21, 17, 34, 11, 55, 89, 6, 9, 12, 16, 18, 24, 36, 48, 72, 144, 233, 29, 377, 10, 61, 122, 305, 610, 47, 141, 329, 987, 1597, 19, 38, 68, 76, 136, 152, 323, 646, 1292, 2584, 37, 113, 4181, 15, 33, 41, 123, 165, 205, 451, 615, 1353, 2255, 6765, 26
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OFFSET
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2,2
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COMMENTS
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A permutation of the natural numbers, ordered by A001177 and ties broken by the number itself. Inverse permutation is A119745. - Martin Fuller, Sep 10 2006
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LINKS
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EXAMPLE
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Fibonacci(9) = 34; and the divisors of 34 are 1, 2, 17 and 34. Of these divisors, 1 and 2 occur earlier in the array.
So the 9th row of the array is [17, 34].
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MATHEMATICA
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f[t_] := Append[t, Select[Divisors[Fibonacci[Length[t] + 1]], FreeQ[Flatten[t], # ] &]]; Flatten@Nest[f, {}, 20] (* Ray Chandler, Jun 14 2006 *)
DeleteDuplicates[Flatten[Divisors[Fibonacci[Range[30]]]]] (* Harvey P. Dale, Apr 13 2020 *)
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CROSSREFS
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KEYWORD
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nonn,tabf
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AUTHOR
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EXTENSIONS
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STATUS
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approved
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