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a(n) = number of terms in the n-th row of A120255(n) = number of terms in A001177 equal to n.
4

%I #13 Oct 11 2019 15:06:08

%S 1,0,1,1,1,2,1,2,2,2,1,10,1,2,5,4,1,10,3,11,5,2,1,55,4,2,12,11,1,52,3,

%T 8,5,2,5,133,7,4,5,46,3,52,1,27,22,6,1,260,6,40,5,11,3,100,13,78,27,6,

%U 3,874,3,4,22,48,5,52,7,27,29,116,3,1319,3,8,36,23,13,116,3,444,112,4,1,1834

%N a(n) = number of terms in the n-th row of A120255(n) = number of terms in A001177 equal to n.

%H T. D. Noe, <a href="/A120256/b120256.txt">Table of n, a(n) for n=1..300</a>

%e Fibonacci(9) = 34; and the divisors of 34 are 1, 2, 17 and 34. Of these divisors, 1 and 2 divide earlier Fibonacci numbers, 17 and 34 do not. So a(9) = 2.

%t f[t_] := Append[t, Select[Divisors[Fibonacci[Length[t] + 1]], FreeQ[Flatten[t], # ] &]]; Length /@ Nest[f, {}, 85] (* _Ray Chandler_, Jun 14 2006 *)

%Y Cf. A120255, A001177.

%K nonn

%O 1,6

%A _Leroy Quet_, Jun 13 2006

%E Extended by _Ray Chandler_, Jun 14 2006