n | a(n) |
---|---|
1 | 0 |
2 | 8 |
3 | 50 |
4 | 313 |
5 | 1980 |
6 | 12494 |
7 | 78880 |
8 | 497940 |
9 | 3143384 |
10 | 19843336 |
11 | 125265720 |
12 | 790768832 |
13 | 4991910856 |
14 | 31512587760 |
15 | 198930468440 |
16 | 1255794385648 |
17 | 7927491165000 |
18 | 50044112904464 |
19 | 315914982635800 |
20 | 1994286049109040 |
21 | 12589389751704584 |
[0,8,50,313,1980,12494,78880,497940,3143384, 19843336,125265720,790768832,4991910856, 31512587760,198930468440,1255794385648, 7927491165000,50044112904464,315914982635800, 1994286049109040,12589389751704584] |