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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 2 |
| 2 | 10 |
| 3 | 79 |
| 4 | 777 |
| 5 | 8606 |
| 6 | 102512 |
| 7 | 1282129 |
| 8 | 16605538 |
| 9 | 220781427 |
| 10 | 2995985345 |
| 11 | 41325515589 |
| 12 | 577713950666 |
| 13 | 8166924383923 |
| 14 | 116550061698966 |
| 15 | 1676836298476274 |
| 16 | 24295472856858786 |
| 17 | 354190017808427947 |
| 18 | 5191706917095917442 |
| 19 | 76469028773023897070 |
| 20 | 1131207622704483680933 |
| 21 | 16799374652884761512521 |
[1,2,10,79,777,8606,102512,1282129,16605538, 220781427,2995985345,41325515589,577713950666, 8166924383923,116550061698966,1676836298476274, 24295472856858786,354190017808427947, 5191706917095917442,76469028773023897070, 1131207622704483680933,16799374652884761512521] |