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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 2 |
| 2 | 9 |
| 3 | 58 |
| 4 | 389 |
| 5 | 3186 |
| 6 | 29437 |
| 7 | 294554 |
| 8 | 3233673 |
| 9 | 38350594 |
| 10 | 484794641 |
| 11 | 6522118362 |
| 12 | 92857444429 |
| 13 | 1390937221298 |
| 14 | 21858658599429 |
| 15 | 359271578140666 |
| 16 | 6156249977141777 |
| 17 | 109722278546645634 |
| 18 | 2029772196329985433 |
| 19 | 38893956306343711994 |
| 20 | 770622936760496106261 |
| 21 | 15763542538016019828082 |
[1,2,9,58,389,3186,29437,294554,3233673,38350594, 484794641,6522118362,92857444429,1390937221298, 21858658599429,359271578140666,6156249977141777, 109722278546645634,2029772196329985433, 38893956306343711994,770622936760496106261, 15763542538016019828082] |