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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 2 |
| 3 | 6 |
| 4 | 182 |
| 5 | 330 |
| 6 | 850 |
| 7 | 2150 |
| 8 | 5964 |
| 9 | 23028 |
| 10 | 85800 |
| 11 | 168150 |
| 12 | 172250 |
| 13 | 179850 |
| 14 | 308700 |
| 15 | 391300 |
| 16 | 484692 |
| 17 | 507725 |
| 18 | 1098750 |
| 19 | 1248148 |
| 20 | 1377075 |
| 21 | 3105218 |
| 22 | 4723500 |
| 23 | 9547650 |
| 24 | 17353350 |
| 25 | 22058792 |
| 26 | 37465350 |
| 27 | 47094425 |
| 28 | 54658450 |
| 29 | 110019000 |
| 30 | 144820200 |
[1,2,6,182,330,850,2150,5964,23028,85800,168150, 172250,179850,308700,391300,484692,507725,1098750, 1248148,1377075,3105218,4723500,9547650,17353350, 22058792,37465350,47094425,54658450,110019000, 144820200] |