n | a(n) |
---|---|
0 | 1 |
1 | 6 |
2 | 45 |
3 | 360 |
4 | 2970 |
5 | 24948 |
6 | 212058 |
7 | 1817640 |
8 | 15677145 |
9 | 135868590 |
10 | 1182056733 |
11 | 10316131488 |
12 | 90266150520 |
13 | 791564704560 |
14 | 6954461332920 |
15 | 61199259729696 |
16 | 539318476367946 |
17 | 4758692438540700 |
18 | 42035116540442850 |
19 | 371678925199705200 |
20 | 3289358488017391020 |
[1,6,45,360,2970,24948,212058,1817640,15677145, 135868590,1182056733,10316131488,90266150520, 791564704560,6954461332920,61199259729696, 539318476367946,4758692438540700, 42035116540442850,371678925199705200, 3289358488017391020] |