A272122 a(n) is the number of positive divisors of A003266(n).

1, 1, 2, 4, 8, 20, 40, 120, 288, 864, 1728, 4800, 9600, 28800, 84480, 304128, 608256, 2322432, 9289728, 40642560, 116121600, 348364800, 696729600, 3185049600, 8918138880, 26754416640, 149824733184, 624269721600, 1248539443200, 6522981580800, 26091926323200, 107629196083200

Offset

1,3

Links

Amiram Eldar, Table of n, a(n) for n = 1..794

Formula

a(n) = A000005(A003266(n)).

a(n+1) = 2*a(n) when n is in A069744.

Mathematica

a[n_] := DivisorSigma[0, Fibonorial[n]]; Array[a, 32] (* Amiram Eldar, Aug 09 2022 *)

Prog

(PARI) a(n) = numdiv(prod(k=1, n, fibonacci(k)));

Crossrefs

Cf. A000005, A000045, A003266, A027423, A063375, A069744, A260622.

Sequence in context: A282953 A283047 A236397 * A323019 A105319 A051389

Adjacent sequences: A272119 A272120 A272121 * A272123 A272124 A272125

Keyword

nonn,easy

Author

Altug Alkan, Apr 28 2016

Status

approved