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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 1 |
| 2 | 5 |
| 3 | 44 |
| 4 | 566 |
| 5 | 9674 |
| 6 | 207166 |
| 7 | 5343456 |
| 8 | 161405016 |
| 9 | 5591409720 |
| 10 | 218592034584 |
| 11 | 9521490534720 |
| 12 | 457329182411856 |
| 13 | 24014921905589328 |
| 14 | 1368772939062117936 |
| 15 | 84161443919543331840 |
| 16 | 5553011951023694408064 |
| 17 | 391360838810043628416384 |
| 18 | 29342876851060951124158848 |
[1,1,5,44,566,9674,207166,5343456,161405016, 5591409720,218592034584,9521490534720, 457329182411856,24014921905589328, 1368772939062117936,84161443919543331840, 5553011951023694408064,391360838810043628416384, 29342876851060951124158848] |