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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 1 |
| 2 | 2 |
| 3 | 4 |
| 4 | 11 |
| 5 | 30 |
| 6 | 96 |
| 7 | 303 |
| 8 | 1029 |
| 9 | 3503 |
| 10 | 12545 |
| 11 | 45113 |
| 12 | 167408 |
| 13 | 623906 |
| 14 | 2378074 |
| 15 | 9109462 |
| 16 | 35460401 |
| 17 | 138679512 |
| 18 | 548909493 |
| 19 | 2182414131 |
| 20 | 8757633284 |
| 21 | 35287783051 |
| 22 | 143225649827 |
| 23 | 583526061368 |
| 24 | 2391378062528 |
| 25 | 9833988357144 |
| 26 | 40635483278352 |
| 27 | 168436746650379 |
| 28 | 701005791862862 |
| 29 | 2925735406975962 |
[1,1,2,4,11,30,96,303,1029,3503,12545,45113, 167408,623906,2378074,9109462,35460401,138679512, 548909493,2182414131,8757633284,35287783051, 143225649827,583526061368,2391378062528, 9833988357144,40635483278352,168436746650379, 701005791862862,2925735406975962] |