n | a(n) |
---|---|
0 | 1 |
1 | 1 |
2 | 3 |
3 | 12 |
4 | 44 |
5 | 264 |
6 | 1020 |
7 | 8160 |
8 | 19680 |
9 | 55104 |
10 | 182784 |
11 | 2193408 |
12 | 4608000 |
13 | 64512000 |
14 | 210524160 |
15 | 560849520 |
16 | 964157040 |
17 | 17354826720 |
18 | 32092508448 |
19 | 641850168960 |
20 | 1302952210560 |
21 | 3134374548480 |
22 | 9806680558080 |
23 | 235360333393920 |
24 | 374108929689600 |
25 | 740882390169600 |
[1,1,3,12,44,264,1020,8160,19680,55104,182784, 2193408,4608000,64512000,210524160,560849520, 964157040,17354826720,32092508448,641850168960, 1302952210560,3134374548480,9806680558080, 235360333393920,374108929689600,740882390169600] |