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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 1 |
| 3 | 4 |
| 4 | 32 |
| 5 | 436 |
| 6 | 9011 |
| 7 | 262731 |
| 8 | 10269469 |
| 9 | 518213374 |
| 10 | 32791782443 |
| 11 | 2542620052511 |
| 12 | 237076215199362 |
| 13 | 26169956408743147 |
| 14 | 3375253146527926664 |
| 15 | 502930199914263085965 |
| 16 | 85738904081626809938925 |
| 17 | 16581476316696251513176624 |
| 18 | 3610682865074032031867899316 |
[1,1,4,32,436,9011,262731,10269469,518213374, 32791782443,2542620052511,237076215199362, 26169956408743147,3375253146527926664, 502930199914263085965,85738904081626809938925, 16581476316696251513176624, 3610682865074032031867899316] |