A133021 - OEIS

%I #19 Nov 15 2024 12:56:06

%S 1,1,1,2,1,3,1,5,1,2,4,8,1,13,1,3,7,21,1,2,17,34,1,5,11,55,1,89,1,2,3,

%T 4,6,8,9,12,16,18,24,36,48,72,144,1,233,1,13,29,377,1,2,5,10,61,122,

%U 305,610,1,3,7,21,47,141,329,987,1,1597

%N Irregular triangle read by rows: row n lists divisors of n-th Fibonacci number A000045(n).

%H T. D. Noe, <a href="/A133021/b133021.txt">Rows n = 1..100 of irregular triangle, flattened</a>

%e Triangle begins:

%e     [ 1 ],

%e     [ 1 ],

%e     [ 1, 2 ],

%e     [ 1, 3 ],

%e     [ 1, 5 ],

%e     [ 1, 2, 4, 8 ],

%e     [ 1, 13 ],

%e     [ 1, 3, 7, 21 ],

%e     [ 1, 2, 17, 34 ],

%e     [ 1, 5, 11, 55 ],

%e     [ 1, 89 ],

%t Flatten[Table[Divisors[Fibonacci[n]], {n, 20}]] (* _T. D. Noe_, Mar 14 2014 *)

%o (Magma) /* As triangle */ [Divisors(Fibonacci(n)): n in [1..30]]; // _Vincenzo Librandi_, Nov 15 2024

%Y Cf. A000045 (Fibonacci numbers), A027750, A063375 (row lengths).

%K nonn,tabf,look

%O 1,4

%A _Omar E. Pol_, Oct 26 2007