n | a(n) |
---|---|
0 | 3 |
1 | 20 |
2 | 118 |
3 | 664 |
4 | 3660 |
5 | 19984 |
6 | 108632 |
7 | 589280 |
8 | 3193392 |
9 | 17297216 |
10 | 93670240 |
11 | 507200896 |
12 | 2746223808 |
13 | 14868977920 |
14 | 80504690048 |
15 | 435871829504 |
16 | 2359908975360 |
17 | 12777066189824 |
18 | 69177803863552 |
19 | 374543504250880 |
[3,20,118,664,3660,19984,108632,589280,3193392, 17297216,93670240,507200896,2746223808, 14868977920,80504690048,435871829504, 2359908975360,12777066189824,69177803863552, 374543504250880] |