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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 2 |
| 2 | 7 |
| 3 | 12 |
| 4 | 34 |
| 5 | 60 |
| 6 | 155 |
| 7 | 280 |
| 8 | 686 |
| 9 | 1260 |
| 10 | 2982 |
| 11 | 5544 |
| 12 | 12804 |
| 13 | 24024 |
| 14 | 54483 |
| 15 | 102960 |
| 16 | 230230 |
| 17 | 437580 |
| 18 | 967538 |
| 19 | 1847560 |
| 20 | 4047836 |
| 21 | 7759752 |
| 22 | 16871582 |
| 23 | 32449872 |
| 24 | 70100044 |
| 25 | 135207800 |
| 26 | 290473900 |
| 27 | 561632400 |
| 28 | 1200823560 |
| 29 | 2326762800 |
[1,2,7,12,34,60,155,280,686,1260,2982,5544,12804, 24024,54483,102960,230230,437580,967538,1847560, 4047836,7759752,16871582,32449872,70100044, 135207800,290473900,561632400,1200823560, 2326762800] |