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| n | a(n) |
|---|---|
| 1 | 310 |
| 2 | 1136 |
| 3 | 4456 |
| 4 | 27168 |
| 5 | 133392 |
| 6 | 607008 |
| 7 | 3503136 |
| 8 | 17206032 |
| 9 | 78302496 |
| 10 | 451903008 |
| 11 | 2219576592 |
| 12 | 10101020448 |
| 13 | 58295486496 |
| 14 | 286325378832 |
| 15 | 1303031636256 |
| 16 | 7520117756448 |
| 17 | 36935973867792 |
| 18 | 168091081075488 |
| 19 | 970095190580256 |
[310,1136,4456,27168,133392,607008,3503136, 17206032,78302496,451903008,2219576592, 10101020448,58295486496,286325378832, 1303031636256,7520117756448,36935973867792, 168091081075488,970095190580256] |