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A120255 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.

%I A120255 #19 Apr 13 2020 15:39:57
%S A120255 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 A120255 29,377,10,61,122,305,610,47,141,329,987,1597,19,38,68,76,136,152,323,
%U A120255 646,1292,2584,37,113,4181,15,33,41,123,165,205,451,615,1353,2255,6765,26
%N A120255 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 A120255 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 A120255 Michael De Vlieger, <a href="/A120255/b120255.txt">Table of n, a(n) for n = 2..12333</a> (rows 2 <= n <= 100)
%e A120255 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 A120255 So the 9th row of the array is [17, 34].
%t A120255 f[t_] := Append[t, Select[Divisors[Fibonacci[Length[t] + 1]], FreeQ[Flatten[t], # ] &]]; Flatten@Nest[f, {}, 20] (* _Ray Chandler_, Jun 14 2006 *)
%t A120255 DeleteDuplicates[Flatten[Divisors[Fibonacci[Range[30]]]]] (* _Harvey P. Dale_, Apr 13 2020 *)
%Y A120255 Cf. A001177, A119745, A120256.
%K A120255 nonn,tabf
%O A120255 2,2
%A A120255 _Leroy Quet_, Jun 13 2006
%E A120255 Extended by _Ray Chandler_, Jun 14 2006