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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 3 |
| 3 | 6 |
| 4 | 16 |
| 5 | 88 |
| 6 | 534 |
| 7 | 4001 |
| 8 | 49783 |
| 9 | 802282 |
| 10 | 16846980 |
| 11 | 518093110 |
| 12 | 21604679482 |
| 13 | 1210757513851 |
| 14 | 95028176738441 |
| 15 | 10229389014494032 |
| 16 | 1500221649654979714 |
| 17 | 303756994018728446946 |
| 18 | 84493641616490831589232 |
[1,3,6,16,88,534,4001,49783,802282,16846980, 518093110,21604679482,1210757513851, 95028176738441,10229389014494032, 1500221649654979714,303756994018728446946, 84493641616490831589232] |