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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 2 |
| 2 | 5 |
| 3 | 23 |
| 4 | 101 |
| 5 | 511 |
| 6 | 3300 |
| 7 | 20499 |
| 8 | 147249 |
| 9 | 1158047 |
| 10 | 9284124 |
| 11 | 82250155 |
| 12 | 762408746 |
| 13 | 7406758725 |
| 14 | 75928931645 |
| 15 | 815389826454 |
| 16 | 9127145085135 |
| 17 | 106002459387831 |
| 18 | 1287304713397098 |
| 19 | 16132127163478581 |
| 20 | 209381715443456410 |
| 21 | 2814011969429674997 |
| 22 | 38957100435462040565 |
[1,2,5,23,101,511,3300,20499,147249,1158047, 9284124,82250155,762408746,7406758725,75928931645, 815389826454,9127145085135,106002459387831, 1287304713397098,16132127163478581, 209381715443456410,2814011969429674997, 38957100435462040565] |