n | a(n) |
---|---|
1 | 1 |
2 | 2 |
3 | 6 |
4 | 20 |
5 | 85 |
6 | 402 |
7 | 2464 |
8 | 15752 |
9 | 119655 |
10 | 976190 |
11 | 9331894 |
12 | 91769988 |
13 | 1077214879 |
14 | 12570658310 |
15 | 168390947820 |
16 | 2337860163248 |
17 | 35513649943201 |
18 | 544140329564898 |
19 | 9660558198790510 |
20 | 166372364728477220 |
[1,2,6,20,85,402,2464,15752,119655,976190,9331894, 91769988,1077214879,12570658310,168390947820, 2337860163248,35513649943201,544140329564898, 9660558198790510,166372364728477220] |