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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 10 |
| 3 | 93 |
| 4 | 836 |
| 5 | 7355 |
| 6 | 63750 |
| 7 | 546553 |
| 8 | 4646920 |
| 9 | 39250935 |
| 10 | 329789450 |
| 11 | 2758868981 |
| 12 | 22995369996 |
| 13 | 191074697203 |
| 14 | 1583463268366 |
| 15 | 13092015636465 |
| 16 | 108024564809744 |
| 17 | 889730213085167 |
| 18 | 7316434446188562 |
| 19 | 60078376613838829 |
| 20 | 492692533579612180 |
[1,10,93,836,7355,63750,546553,4646920,39250935, 329789450,2758868981,22995369996,191074697203, 1583463268366,13092015636465,108024564809744, 889730213085167,7316434446188562, 60078376613838829,492692533579612180] |