A056042 - cp's OEIS frontend

A056042 a(n) = n!/(k!)^2, where k is the largest number such that (k!)^2 divides n!.

n	a(n)
1	1
2	2
3	6
4	6
5	30
6	20
7	140
8	70
9	630
10	7
11	77
12	924
13	12012
14	3432
15	51480
16	12870
17	218790
18	48620
19	923780
20	184756
21	3879876
22	705432
23	16224936
24	2704156
25	67603900
26	10400600
27	280816200
28	178296
29	5170584
30	155117520
31	4808643120
32	601080390
33	19835652870

[1, 2, 6, 6, 30, 20, 140, 70, 630, 7, 77, 924, 12012, 3432, 51480, 12870, 218790, 48620, 923780, 184756, 3879876, 705432, 16224936, 2704156, 67603900, 10400600, 280816200, 178296, 5170584, 155117520, 4808643120, 601080390, 19835652870]

cp's OEIS Frontend

A056042 a(n) = n!/(k!)^2, where k is the largest number such that (k!)^2 divides n!.

Table of values

List of values