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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 1 |
| 2 | 2 |
| 3 | 3 |
| 4 | 10 |
| 5 | 22 |
| 6 | 65 |
| 7 | 152 |
| 8 | 509 |
| 9 | 1466 |
| 10 | 4645 |
| 11 | 13532 |
| 12 | 44434 |
| 13 | 146454 |
| 14 | 483958 |
| 15 | 1573257 |
| 16 | 5245446 |
| 17 | 18189431 |
| 18 | 62918036 |
| 19 | 215842095 |
| 20 | 743114400 |
| 21 | 2625979396 |
| 22 | 9395162641 |
| 23 | 33370716692 |
| 24 | 118291958507 |
| 25 | 424227452507 |
| 26 | 1546163643295 |
| 27 | 5636678152183 |
| 28 | 20454730175647 |
| 29 | 74489593325489 |
| 30 | 274498234923989 |
| 31 | 1018318442708743 |
[1,1,2,3,10,22,65,152,509,1466,4645,13532,44434, 146454,483958,1573257,5245446,18189431,62918036, 215842095,743114400,2625979396,9395162641, 33370716692,118291958507,424227452507, 1546163643295,5636678152183,20454730175647, 74489593325489,274498234923989,1018318442708743] |