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| n | a(n) |
|---|---|
| 1 | 1172 |
| 2 | 4616 |
| 3 | 18444 |
| 4 | 76112 |
| 5 | 319156 |
| 6 | 1374400 |
| 7 | 5998924 |
| 8 | 26765648 |
| 9 | 120643572 |
| 10 | 553515168 |
| 11 | 2557495628 |
| 12 | 11985104432 |
| 13 | 56413124340 |
| 14 | 268564680000 |
| 15 | 1281524215500 |
| 16 | 6172279073168 |
| 17 | 29750350541044 |
| 18 | 144526879218144 |
| 19 | 701822038872140 |
[1172,4616,18444,76112,319156,1374400,5998924, 26765648,120643572,553515168,2557495628, 11985104432,56413124340,268564680000, 1281524215500,6172279073168,29750350541044, 144526879218144,701822038872140] |