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| n | a(n) |
|---|---|
| 0 | 0 |
| 1 | 1 |
| 2 | 10 |
| 3 | 81 |
| 4 | 652 |
| 5 | 5545 |
| 6 | 50886 |
| 7 | 506905 |
| 8 | 5480056 |
| 9 | 64116657 |
| 10 | 808856290 |
| 11 | 10959016321 |
| 12 | 158851484100 |
| 13 | 2454385635481 |
| 14 | 40285778016862 |
| 15 | 700261611998985 |
| 16 | 12853532939027056 |
| 17 | 248482678808005345 |
| 18 | 5047002269952482106 |
| 19 | 107466341437781300017 |
| 20 | 2394019421567804960380 |
[0,1,10,81,652,5545,50886,506905,5480056,64116657, 808856290,10959016321,158851484100,2454385635481, 40285778016862,700261611998985,12853532939027056, 248482678808005345,5047002269952482106, 107466341437781300017,2394019421567804960380] |