| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 1 |
| 2 | 2 |
| 3 | 8 |
| 4 | 46 |
| 5 | 322 |
| 6 | 2546 |
| 7 | 21870 |
| 8 | 199494 |
| 9 | 1904624 |
| 10 | 18846714 |
| 11 | 191955370 |
| 12 | 2002141126 |
| 13 | 21303422480 |
| 14 | 230553207346 |
| 15 | 2531848587534 |
| 16 | 28159614749270 |
| 17 | 316713536035464 |
| 18 | 3597509926531778 |
| 19 | 41225699113145888 |
| 20 | 476180721050626814 |
| 21 | 5539597373695447322 |
| 22 | 64863295574835126394 |
| 23 | 763984568163192551672 |
| 24 | 9047263176444565467566 |
[1,1,2,8,46,322,2546,21870,199494,1904624, 18846714,191955370,2002141126,21303422480, 230553207346,2531848587534,28159614749270, 316713536035464,3597509926531778, 41225699113145888,476180721050626814, 5539597373695447322,64863295574835126394, 763984568163192551672,9047263176444565467566] |