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| n | a(n) |
|---|---|
| 0 | 0 |
| 1 | 455 |
| 2 | 13072 |
| 3 | 111111 |
| 4 | 536312 |
| 5 | 1864135 |
| 6 | 5227320 |
| 7 | 12597767 |
| 8 | 27126736 |
| 9 | 53543367 |
| 10 | 98611520 |
| 11 | 171644935 |
| 12 | 285080712 |
| 13 | 455111111 |
| 14 | 702373672 |
| 15 | 1052699655 |
| 16 | 1537920800 |
| 17 | 2196734407 |
| 18 | 3075626736 |
| 19 | 4229854727 |
| 20 | 5724486040 |
| 21 | 7635497415 |
| 22 | 10050931352 |
| 23 | 13072111111 |
| 24 | 16814914032 |
| 25 | 21411103175 |
| 26 | 27009717280 |
[0,455,13072,111111,536312,1864135,5227320, 12597767,27126736,53543367,98611520,171644935, 285080712,455111111,702373672,1052699655, 1537920800,2196734407,3075626736,4229854727, 5724486040,7635497415,10050931352,13072111111, 16814914032,21411103175,27009717280] |