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| n | a(n) |
|---|---|
| 1 | 0 |
| 2 | 40 |
| 3 | 428 |
| 4 | 6752 |
| 5 | 47592 |
| 6 | 225488 |
| 7 | 826488 |
| 8 | 2696652 |
| 9 | 7451396 |
| 10 | 19200532 |
| 11 | 44634008 |
| 12 | 96779936 |
| 13 | 196510032 |
| 14 | 380589596 |
| 15 | 700636600 |
| 16 | 1243173684 |
| 17 | 2124664616 |
| 18 | 3523145424 |
| 19 | 5673664032 |
| 20 | 8921020564 |
| 21 | 13691990956 |
| 22 | 20604281544 |
| 23 | 30407094956 |
| 24 | 44122851304 |
[0,40,428,6752,47592,225488,826488,2696652, 7451396,19200532,44634008,96779936,196510032, 380589596,700636600,1243173684,2124664616, 3523145424,5673664032,8921020564,13691990956, 20604281544,30407094956,44122851304] |