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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 0 |
| 2 | 1 |
| 3 | 9 |
| 4 | 162 |
| 5 | 4527 |
| 6 | 172335 |
| 7 | 7861940 |
| 8 | 416446379 |
| 9 | 25076668511 |
| 10 | 1692214417496 |
| 11 | 126525497074469 |
| 12 | 10384653020019554 |
| 13 | 928348695659951013 |
| 14 | 89797089935616345473 |
| 15 | 9344984104905250973209 |
| 16 | 1041167026926648579218267 |
| 17 | 123655975822561996200923033 |
| 18 | 15595901625395079379351443550 |
[1,0,1,9,162,4527,172335,7861940,416446379, 25076668511,1692214417496,126525497074469, 10384653020019554,928348695659951013, 89797089935616345473,9344984104905250973209, 1041167026926648579218267, 123655975822561996200923033, 15595901625395079379351443550] |