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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 2 |
| 2 | 9 |
| 3 | 58 |
| 4 | 436 |
| 5 | 3572 |
| 6 | 30935 |
| 7 | 278532 |
| 8 | 2581043 |
| 9 | 24453404 |
| 10 | 235790159 |
| 11 | 2306367444 |
| 12 | 22829030276 |
| 13 | 228240387070 |
| 14 | 2301498462245 |
| 15 | 23379656027868 |
| 16 | 239038022347243 |
| 17 | 2457891085704180 |
| 18 | 25400777844198274 |
| 19 | 263685720722690420 |
| 20 | 2748421883496133866 |
[1,2,9,58,436,3572,30935,278532,2581043,24453404, 235790159,2306367444,22829030276,228240387070, 2301498462245,23379656027868,239038022347243, 2457891085704180,25400777844198274, 263685720722690420,2748421883496133866] |