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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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%I #19 Apr 13 2020 15:39:57

%S 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,

%T 29,377,10,61,122,305,610,47,141,329,987,1597,19,38,68,76,136,152,323,

%U 646,1292,2584,37,113,4181,15,33,41,123,165,205,451,615,1353,2255,6765,26

%N 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.

%C 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

%H Michael De Vlieger, <a href="/A120255/b120255.txt">Table of n, a(n) for n = 2..12333</a> (rows 2 <= n <= 100)

%e 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.

%e So the 9th row of the array is [17, 34].

%t f[t_] := Append[t, Select[Divisors[Fibonacci[Length[t] + 1]], FreeQ[Flatten[t], # ] &]]; Flatten@Nest[f, {}, 20] (* _Ray Chandler_, Jun 14 2006 *)

%t DeleteDuplicates[Flatten[Divisors[Fibonacci[Range[30]]]]] (* _Harvey P. Dale_, Apr 13 2020 *)

%Y Cf. A001177, A119745, A120256.

%K nonn,tabf

%O 2,2

%A _Leroy Quet_, Jun 13 2006

%E Extended by _Ray Chandler_, Jun 14 2006