| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 1 |
| 2 | 3 |
| 3 | 10 |
| 4 | 45 |
| 5 | 221 |
| 6 | 1315 |
| 7 | 8324 |
| 8 | 60809 |
| 9 | 464113 |
| 10 | 3993811 |
| 11 | 35342814 |
| 12 | 349085869 |
| 13 | 3486862653 |
| 14 | 38870528411 |
| 15 | 429139127416 |
| 16 | 5345350992113 |
| 17 | 63994963427393 |
| 18 | 887692696733827 |
| 19 | 11284513262684914 |
| 20 | 175285847038616301 |
| 21 | 2298693217837384957 |
| 22 | 40805829165456572691 |
[1,1,3,10,45,221,1315,8324,60809,464113,3993811, 35342814,349085869,3486862653,38870528411, 429139127416,5345350992113,63994963427393, 887692696733827,11284513262684914, 175285847038616301,2298693217837384957, 40805829165456572691] |