A325639 - OEIS

A325639 as a simple table

n	a(n)
1	1
2	6
3	28
4	120
5	312
6	428
7	456
8	496
9	504
10	672
11	760
12	6552
13	8128
14	30240
15	31452
16	32760
17	429240
18	523776
19	2178540
20	5009850
21	7505976
22	23569920
23	33550336
24	45532800
25	142990848
26	186076800
27	379975680

[1,6,28,120,312,428,456,496,504,672,760,6552,8128, 30240,31452,32760,429240,523776,2178540,5009850, 7505976,23569920,33550336,45532800,142990848, 186076800,379975680]