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| n | a(n) |
|---|---|
| 1 | 144 |
| 2 | 772 |
| 3 | 3984 |
| 4 | 20936 |
| 5 | 108864 |
| 6 | 570208 |
| 7 | 2971200 |
| 8 | 15541312 |
| 9 | 81063040 |
| 10 | 423704496 |
| 11 | 2211225408 |
| 12 | 11553144144 |
| 13 | 60311293088 |
| 14 | 315043601664 |
| 15 | 1644900877696 |
| 16 | 8591310050640 |
| 17 | 44860831279136 |
| 18 | 234292373710800 |
| 19 | 1223453493401024 |
[144,772,3984,20936,108864,570208,2971200, 15541312,81063040,423704496,2211225408, 11553144144,60311293088,315043601664, 1644900877696,8591310050640,44860831279136, 234292373710800,1223453493401024] |