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| n | a(n) |
|---|---|
| 1 | 0 |
| 2 | 0 |
| 3 | 0 |
| 4 | 0 |
| 5 | 0 |
| 6 | 0 |
| 7 | 0 |
| 8 | 0 |
| 9 | 166 |
| 10 | 4902 |
| 11 | 54771 |
| 12 | 382439 |
| 13 | 1976455 |
| 14 | 8250687 |
| 15 | 29309540 |
| 16 | 91705972 |
| 17 | 258870740 |
| 18 | 671005444 |
| 19 | 1618468198 |
| 20 | 3670491998 |
| 21 | 7891420850 |
| 22 | 16191666766 |
| 23 | 31878943876 |
| 24 | 60501909500 |
| 25 | 111108316262 |
| 26 | 198083991586 |
| 27 | 343784805209 |
[0,0,0,0,0,0,0,0,166,4902,54771,382439,1976455, 8250687,29309540,91705972,258870740,671005444, 1618468198,3670491998,7891420850,16191666766, 31878943876,60501909500,111108316262,198083991586, 343784805209] |