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| n | a(n) |
|---|---|
| 0 | 0 |
| 1 | 0 |
| 2 | 0 |
| 3 | 0 |
| 4 | 0 |
| 5 | 1 |
| 6 | 2 |
| 7 | 3 |
| 8 | 4 |
| 9 | 10 |
| 10 | 21 |
| 11 | 32 |
| 12 | 43 |
| 13 | 54 |
| 14 | 165 |
| 15 | 276 |
| 16 | 387 |
| 17 | 498 |
| 18 | 1109 |
| 19 | 2220 |
| 20 | 3331 |
| 21 | 4442 |
| 22 | 5553 |
| 23 | 16664 |
| 24 | 27775 |
| 25 | 38886 |
| 26 | 49997 |
| 27 | 111108 |
| 28 | 222219 |
| 29 | 333330 |
| 30 | 444441 |
| 31 | 555552 |
| 32 | 666663 |
[0,0,0,0,0,1,2,3,4,10,21,32,43,54,165,276,387,498, 1109,2220,3331,4442,5553,16664,27775,38886,49997, 111108,222219,333330,444441,555552,666663] |