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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 1 |
| 2 | 2 |
| 3 | 21 |
| 4 | 596 |
| 5 | 32805 |
| 6 | 2960496 |
| 7 | 396523540 |
| 8 | 73803150440 |
| 9 | 18216533196693 |
| 10 | 5757491981210470 |
| 11 | 2267526164705341925 |
| 12 | 1088820552191787545688 |
| 13 | 626169526288460672060244 |
| 14 | 424903177461959840892846066 |
| 15 | 335946105815409394263421836000 |
| 16 | 306145042287138023678922165314512 |
[1,1,2,21,596,32805,2960496,396523540,73803150440, 18216533196693,5757491981210470, 2267526164705341925,1088820552191787545688, 626169526288460672060244, 424903177461959840892846066, 335946105815409394263421836000, 306145042287138023678922165314512] |