n | a(n) |
---|---|
1 | 1 |
2 | 1 |
3 | 4 |
4 | 15 |
5 | 65 |
6 | 291 |
7 | 1356 |
8 | 6474 |
9 | 31555 |
10 | 156315 |
11 | 784924 |
12 | 3986534 |
13 | 20444676 |
14 | 105728100 |
15 | 550735400 |
16 | 2886924190 |
17 | 15217019595 |
18 | 80600822575 |
19 | 428766983300 |
20 | 2289637381800 |
21 | 12268642450420 |
22 | 65941128441080 |
23 | 355396218177760 |
24 | 1920215555772550 |
25 | 10398415258863275 |
[1,1,4,15,65,291,1356,6474,31555,156315,784924, 3986534,20444676,105728100,550735400,2886924190, 15217019595,80600822575,428766983300, 2289637381800,12268642450420,65941128441080, 355396218177760,1920215555772550, 10398415258863275] |