A090221-OEIS公司

A090221号作为一个简单的表

n个	a（n）
4	1
5	96
6	72
7	14400
8	16
9	38400
10	3456000
11	1
12	27000
13	22104000
14	1270080000
15	7200
16	34905600
17	16111872000
18	682795008000
19	856
20	21154176
21	48248363520
22	15279164006400
23	516193026048000
24	48
25	6064128
26	54644474880
27	78083415244800

[1,96,72,14400,16,38400,3456000,1,27000,22104000,1270080000,7200,34905600,16111872000,682795008000,856,21154176,48248363520,15279164006400,516193026048000,48,6064128,54644474880,78083415244800]