A118381 - OEIS

A118381

Largest 3-smooth number dividing n!.

1, 2, 6, 24, 24, 144, 144, 1152, 10368, 20736, 20736, 248832, 248832, 497664, 1492992, 23887872, 23887872, 429981696, 429981696, 1719926784, 5159780352, 10319560704, 10319560704, 247669456896, 247669456896, 495338913792, 13374150672384, 53496602689536, 53496602689536

(list; graph; refs; listen; history; text; internal format)

OFFSET

1,2

LINKS

Amiram Eldar, Table of n, a(n) for n = 1..1861 (terms below 10^1000)

Index entries for sequences related to factorial numbers.

FORMULA

a(n) = A060818(n) * A060828(n).

MATHEMATICA

s[n_, b_] := Sum[IntegerExponent[k, b], {k, 1, n}]; a[n_] := 2^s[n, 2] * 3^s[n, 3]; Array[a, 30] (* Amiram Eldar, Jan 29 2020 *)

CROSSREFS

Cf. A003586, A000142, A011371, A054861, A060818, A060828.