n | a(n) |
---|---|
1 | 1 |
2 | 1 |
3 | 2 |
4 | 6 |
5 | 19 |
6 | 71 |
7 | 274 |
8 | 1117 |
9 | 4650 |
10 | 19819 |
11 | 85710 |
12 | 375712 |
13 | 1664203 |
14 | 7439593 |
15 | 33515758 |
16 | 152019560 |
17 | 693625265 |
18 | 3181528275 |
19 | 14661581030 |
20 | 67850297506 |
21 | 315187646601 |
22 | 1469195636293 |
23 | 6869889703638 |
24 | 32215399021901 |
25 | 151467334017864 |
26 | 713881817440421 |
27 | 3372142139764434 |
[1,1,2,6,19,71,274,1117,4650,19819,85710,375712, 1664203,7439593,33515758,152019560,693625265, 3181528275,14661581030,67850297506,315187646601, 1469195636293,6869889703638,32215399021901, 151467334017864,713881817440421,3372142139764434] |