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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 1 |
| 2 | 3 |
| 3 | 16 |
| 4 | 113 |
| 5 | 996 |
| 6 | 10537 |
| 7 | 130054 |
| 8 | 1834513 |
| 9 | 29111896 |
| 10 | 513307601 |
| 11 | 9955832514 |
| 12 | 210652214665 |
| 13 | 4828548335092 |
| 14 | 119193293536969 |
| 15 | 3152465052989326 |
| 16 | 88935973854834593 |
| 17 | 2665836978234855984 |
| 18 | 84608363388300429601 |
| 19 | 2834484567764492239354 |
| 20 | 99956558270008377397081 |
| 21 | 3701159405682998540166796 |
| 22 | 143571313108884280622221913 |
| 23 | 5822409005523822986360056326 |
[1,1,3,16,113,996,10537,130054,1834513,29111896, 513307601,9955832514,210652214665,4828548335092, 119193293536969,3152465052989326, 88935973854834593,2665836978234855984, 84608363388300429601,2834484567764492239354, 99956558270008377397081,3701159405682998540166796, 143571313108884280622221913, 5822409005523822986360056326] |