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| n | a(n) |
|---|---|
| 1 | 480 |
| 2 | 1060 |
| 3 | 3008 |
| 4 | 9464 |
| 5 | 22576 |
| 6 | 67968 |
| 7 | 192808 |
| 8 | 496088 |
| 9 | 1475768 |
| 10 | 4018720 |
| 11 | 10894120 |
| 12 | 31512000 |
| 13 | 85274000 |
| 14 | 237162184 |
| 15 | 670298216 |
| 16 | 1827175160 |
| 17 | 5121768064 |
| 18 | 14281894072 |
| 19 | 39288809968 |
| 20 | 110061644032 |
| 21 | 305182278280 |
| 22 | 845001830872 |
| 23 | 2359774258680 |
[480,1060,3008,9464,22576,67968,192808,496088, 1475768,4018720,10894120,31512000,85274000, 237162184,670298216,1827175160,5121768064, 14281894072,39288809968,110061644032,305182278280, 845001830872,2359774258680] |