n | a(n) |
---|---|
0 | 0 |
1 | 3 |
2 | 15 |
3 | 84 |
4 | 465 |
5 | 2577 |
6 | 14280 |
7 | 79131 |
8 | 438495 |
9 | 2429868 |
10 | 13464825 |
11 | 74613729 |
12 | 413463120 |
13 | 2291156787 |
14 | 12696173295 |
15 | 70354336836 |
16 | 389860204065 |
17 | 2160364030833 |
18 | 11971400766360 |
19 | 66338095924299 |
20 | 367604681920575 |
[0,3,15,84,465,2577,14280,79131,438495,2429868, 13464825,74613729,413463120,2291156787, 12696173295,70354336836,389860204065, 2160364030833,11971400766360,66338095924299, 367604681920575] |