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| n | a(n) |
|---|---|
| 1 | 0 |
| 2 | 18 |
| 3 | 483 |
| 4 | 8208 |
| 5 | 127603 |
| 6 | 1905024 |
| 7 | 27253740 |
| 8 | 376888612 |
| 9 | 5103365490 |
| 10 | 67844126082 |
| 11 | 888477690822 |
| 12 | 11494561892636 |
| 13 | 147164798869788 |
| 14 | 1867364729867364 |
| 15 | 23511630584230335 |
| 16 | 294017262976224648 |
| 17 | 3654593023686994587 |
[0,18,483,8208,127603,1905024,27253740,376888612, 5103365490,67844126082,888477690822, 11494561892636,147164798869788,1867364729867364, 23511630584230335,294017262976224648, 3654593023686994587] |