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| n | a(n) |
|---|---|
| 1 | 720 |
| 2 | 1888 |
| 3 | 4100 |
| 4 | 9876 |
| 5 | 25012 |
| 6 | 60296 |
| 7 | 148328 |
| 8 | 369360 |
| 9 | 917504 |
| 10 | 2284292 |
| 11 | 5685480 |
| 12 | 14168096 |
| 13 | 35364992 |
| 14 | 88266608 |
| 15 | 220224348 |
| 16 | 549719568 |
| 17 | 1372906300 |
| 18 | 3428376580 |
| 19 | 8559482304 |
| 20 | 21374102868 |
| 21 | 53382093000 |
| 22 | 133313369596 |
| 23 | 332909642184 |
[720,1888,4100,9876,25012,60296,148328,369360, 917504,2284292,5685480,14168096,35364992,88266608, 220224348,549719568,1372906300,3428376580, 8559482304,21374102868,53382093000,133313369596, 332909642184] |