n | a(n) |
---|---|
0 | 1 |
1 | 6 |
2 | 30 |
3 | 145 |
4 | 696 |
5 | 3336 |
6 | 15985 |
7 | 76590 |
8 | 366966 |
9 | 1758241 |
10 | 8424240 |
11 | 40362960 |
12 | 193390561 |
13 | 926589846 |
14 | 4439558670 |
15 | 21271203505 |
16 | 101916458856 |
17 | 488311090776 |
18 | 2339638995025 |
19 | 11209883884350 |
20 | 53709780426726 |
21 | 257339018249281 |
[1,6,30,145,696,3336,15985,76590,366966,1758241, 8424240,40362960,193390561,926589846,4439558670, 21271203505,101916458856,488311090776, 2339638995025,11209883884350,53709780426726, 257339018249281] |