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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 1 |
| 2 | 4 |
| 3 | 33 |
| 4 | 37 |
| 5 | 70 |
| 6 | 457 |
| 7 | 1441 |
| 8 | 4780 |
| 9 | 6221 |
| 10 | 23443 |
| 11 | 29664 |
| 12 | 53107 |
| 13 | 82771 |
| 14 | 218649 |
| 15 | 6642241 |
| 16 | 13503131 |
| 17 | 20145372 |
| 18 | 33648503 |
| 19 | 53793875 |
| 20 | 195030128 |
| 21 | 248824003 |
| 22 | 941502137 |
| 23 | 3073330414 |
| 24 | 19381484621 |
| 25 | 22454815035 |
| 26 | 41836299656 |
| 27 | 357145212283 |
| 28 | 1113271936505 |
| 29 | 1470417148788 |
[1,1,4,33,37,70,457,1441,4780,6221,23443,29664, 53107,82771,218649,6642241,13503131,20145372, 33648503,53793875,195030128,248824003,941502137, 3073330414,19381484621,22454815035,41836299656, 357145212283,1113271936505,1470417148788] |