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| n | a(n) |
|---|---|
| 0 | 0 |
| 1 | 0 |
| 2 | 156 |
| 3 | 14298 |
| 4 | 228984 |
| 5 | 1821420 |
| 6 | 9676020 |
| 7 | 39328086 |
| 8 | 131914608 |
| 9 | 382726584 |
| 10 | 991134540 |
| 11 | 2342199090 |
| 12 | 5133181416 |
| 13 | 10561434468 |
| 14 | 20593784484 |
| 15 | 38341504110 |
| 16 | 68569332960 |
| 17 | 118371718896 |
| 18 | 198054533628 |
| 19 | 322265959434 |
| 20 | 511426049880 |
| 21 | 793510636380 |
| 22 | 1206251784276 |
[0,0,156,14298,228984,1821420,9676020,39328086, 131914608,382726584,991134540,2342199090, 5133181416,10561434468,20593784484,38341504110, 68569332960,118371718896,198054533628, 322265959434,511426049880,793510636380, 1206251784276] |