A002546-OEIS公司

A002546号作为一个简单的表

n个	a（n）
1	1
2	2
三	4
4	8
5	15
6	240
7	15120
8	672
9	8400
10	100800
11	69300
12	4950
13	17199000
14	22422400
15	33633600
16	201801600
17	467812800
18	102918816000
19	410646075840
20	3555377280
21	215100325440
22	5162407810560
23	30920671782000
24	190281057120
25	1085315579548200
26	562756226432400
27	22969641895200

[1,2,4,8,15,240,15120,672,8400,100800,69300,4950,17199000,22422400,33633600,201801600,467812800,102918816000,410646075840,3555377280,215100325440,5162407810560,30920671782000,190281057120,1085315579548200,562756226432400,22969641895200]