n | a(n) |
---|---|
0 | 1 |
1 | 1 |
2 | 2 |
3 | 7 |
4 | 23 |
5 | 72 |
6 | 225 |
7 | 705 |
8 | 2210 |
9 | 6927 |
10 | 21711 |
11 | 68048 |
12 | 213281 |
13 | 668481 |
14 | 2095202 |
15 | 6566935 |
16 | 20582567 |
17 | 64511384 |
18 | 202196289 |
19 | 633738369 |
20 | 1986309058 |
21 | 6225634847 |
22 | 19512839199 |
23 | 61158565024 |
[1,1,2,7,23,72,225,705,2210,6927,21711,68048, 213281,668481,2095202,6566935,20582567,64511384, 202196289,633738369,1986309058,6225634847, 19512839199,61158565024] |