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| n | a(n) |
|---|---|
| 1 | 0 |
| 2 | 1 |
| 3 | 4 |
| 4 | 5 |
| 5 | 21 |
| 6 | 28 |
| 7 | 120 |
| 8 | 165 |
| 9 | 220 |
| 10 | 286 |
| 11 | 1365 |
| 12 | 1820 |
| 13 | 8568 |
| 14 | 11628 |
| 15 | 15504 |
| 16 | 20349 |
| 17 | 100947 |
| 18 | 134596 |
| 19 | 657800 |
| 20 | 888030 |
| 21 | 1184040 |
| 22 | 1560780 |
| 23 | 7888725 |
| 24 | 10518300 |
| 25 | 13884156 |
| 26 | 18156204 |
| 27 | 23535820 |
| 28 | 30260340 |
| 29 | 163011640 |
| 30 | 211915132 |
| 31 | 1121099408 |
| 32 | 1471442973 |
| 33 | 1917334783 |
| 34 | 2481256778 |
| 35 | 3190187286 |
[0,1,4,5,21,28,120,165,220,286,1365,1820,8568, 11628,15504,20349,100947,134596,657800,888030, 1184040,1560780,7888725,10518300,13884156, 18156204,23535820,30260340,163011640,211915132, 1121099408,1471442973,1917334783,2481256778, 3190187286] |