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| n | a(n) |
|---|---|
| 1 | 0 |
| 2 | 1 |
| 3 | 10 |
| 4 | 87 |
| 5 | 742 |
| 6 | 6355 |
| 7 | 54972 |
| 8 | 480676 |
| 9 | 4246156 |
| 10 | 37857609 |
| 11 | 340321820 |
| 12 | 3081805727 |
| 13 | 28089617550 |
| 14 | 257516093302 |
| 15 | 2373098818888 |
| 16 | 21971084873775 |
| 17 | 204274300836144 |
| 18 | 1906474633391853 |
| 19 | 17854760020687254 |
| 20 | 167745930396293263 |
| 21 | 1580556744351118030 |
| 22 | 14932307414985485049 |
| 23 | 141420575129236412394 |
[0,1,10,87,742,6355,54972,480676,4246156,37857609, 340321820,3081805727,28089617550,257516093302, 2373098818888,21971084873775,204274300836144, 1906474633391853,17854760020687254, 167745930396293263,1580556744351118030, 14932307414985485049,141420575129236412394] |