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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 1 |
| 2 | 2 |
| 3 | 4 |
| 4 | 11 |
| 5 | 30 |
| 6 | 91 |
| 7 | 280 |
| 8 | 929 |
| 9 | 3125 |
| 10 | 10912 |
| 11 | 38716 |
| 12 | 141115 |
| 13 | 521666 |
| 14 | 1961738 |
| 15 | 7468828 |
| 16 | 28818382 |
| 17 | 112367258 |
| 18 | 442532489 |
| 19 | 1758198902 |
| 20 | 7044028427 |
| 21 | 28431378496 |
| 22 | 115539205449 |
| 23 | 472502030716 |
| 24 | 1943716565577 |
| 25 | 8039163734201 |
| 26 | 33416716299543 |
| 27 | 139559578867379 |
| 28 | 585418557877110 |
| 29 | 2465785094190391 |
[1,1,2,4,11,30,91,280,929,3125,10912,38716,141115, 521666,1961738,7468828,28818382,112367258, 442532489,1758198902,7044028427,28431378496, 115539205449,472502030716,1943716565577, 8039163734201,33416716299543,139559578867379, 585418557877110,2465785094190391] |