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| n | a(n) |
|---|---|
| 0 | 0 |
| 1 | 1 |
| 2 | 2 |
| 3 | 9 |
| 4 | 12 |
| 5 | 50 |
| 6 | 60 |
| 7 | 245 |
| 8 | 280 |
| 9 | 1134 |
| 10 | 1260 |
| 11 | 5082 |
| 12 | 5544 |
| 13 | 22308 |
| 14 | 24024 |
| 15 | 96525 |
| 16 | 102960 |
| 17 | 413270 |
| 18 | 437580 |
| 19 | 1755182 |
| 20 | 1847560 |
| 21 | 7407036 |
| 22 | 7759752 |
| 23 | 31097794 |
| 24 | 32449872 |
| 25 | 130007500 |
| 26 | 135207800 |
| 27 | 541574100 |
| 28 | 561632400 |
| 29 | 2249204040 |
| 30 | 2326762800 |
| 31 | 9316746045 |
| 32 | 9617286240 |
| 33 | 38504502630 |
[0,1,2,9,12,50,60,245,280,1134,1260,5082,5544, 22308,24024,96525,102960,413270,437580,1755182, 1847560,7407036,7759752,31097794,32449872, 130007500,135207800,541574100,561632400, 2249204040,2326762800,9316746045,9617286240, 38504502630] |