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| n | a(n) |
|---|---|
| 1 | 1140 |
| 2 | 5228 |
| 3 | 22624 |
| 4 | 111552 |
| 5 | 588840 |
| 6 | 3048096 |
| 7 | 16072760 |
| 8 | 84203240 |
| 9 | 442219464 |
| 10 | 2322616208 |
| 11 | 12190484896 |
| 12 | 64028249688 |
| 13 | 336134793648 |
| 14 | 1765105097640 |
| 15 | 9267826715912 |
| 16 | 48663053519336 |
| 17 | 255518422362912 |
| 18 | 1341650195416352 |
[1140,5228,22624,111552,588840,3048096,16072760, 84203240,442219464,2322616208,12190484896, 64028249688,336134793648,1765105097640, 9267826715912,48663053519336,255518422362912, 1341650195416352] |