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| n | a(n) |
|---|---|
| 0 | 0 |
| 1 | 5 |
| 2 | 26 |
| 3 | 75 |
| 4 | 1104 |
| 5 | 3505 |
| 6 | 20312 |
| 7 | 20312 |
| 8 | 4961570 |
| 9 | 28020774 |
| 10 | 229788809 |
| 11 | 512264058 |
| 12 | 2489590801 |
| 13 | 71696026806 |
| 14 | 71696026806 |
| 15 | 71696026806 |
| 16 | 19061942066578 |
| 17 | 218459525484184 |
| 18 | 451090039471391 |
[0,5,26,75,1104,3505,20312,20312,4961570,28020774, 229788809,512264058,2489590801,71696026806, 71696026806,71696026806,19061942066578, 218459525484184,451090039471391] |