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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 1 |
| 2 | 2 |
| 3 | 3 |
| 4 | 4 |
| 5 | 6 |
| 6 | 10 |
| 7 | 20 |
| 8 | 36 |
| 9 | 72 |
| 10 | 162 |
| 11 | 352 |
| 12 | 810 |
| 13 | 1872 |
| 14 | 4480 |
| 15 | 11088 |
| 16 | 27720 |
| 17 | 71280 |
| 18 | 186368 |
| 19 | 496128 |
| 20 | 1347192 |
| 21 | 3720960 |
| 22 | 10407936 |
| 23 | 29576988 |
| 24 | 85322160 |
| 25 | 249500160 |
| 26 | 738904320 |
| 27 | 2216712960 |
| 28 | 6732000000 |
| 29 | 20680540160 |
| 30 | 64257392640 |
| 31 | 201852518400 |
| 32 | 640832000000 |
| 33 | 2055425699250 |
| 34 | 6658777165824 |
| 35 | 21781337550336 |
[1,1,2,3,4,6,10,20,36,72,162,352,810,1872,4480, 11088,27720,71280,186368,496128,1347192,3720960, 10407936,29576988,85322160,249500160,738904320, 2216712960,6732000000,20680540160,64257392640, 201852518400,640832000000,2055425699250, 6658777165824,21781337550336] |