The OEIS is supported by the many generous donors to the OEIS Foundation.
| n | a(n) |
|---|---|
| 0 | 3 |
| 1 | 49 |
| 2 | 462 |
| 3 | 3294 |
| 4 | 19715 |
| 5 | 104517 |
| 6 | 506646 |
| 7 | 2292310 |
| 8 | 9817920 |
| 9 | 40210800 |
| 10 | 158677370 |
| 11 | 606790410 |
| 12 | 2258770689 |
| 13 | 8214432303 |
| 14 | 29269938510 |
| 15 | 102434633406 |
| 16 | 352793077413 |
| 17 | 1197764971911 |
| 18 | 4014411070092 |
[3,49,462,3294,19715,104517,506646,2292310, 9817920,40210800,158677370,606790410,2258770689, 8214432303,29269938510,102434633406,352793077413, 1197764971911,4014411070092] |