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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 1 |
| 2 | 5 |
| 3 | 25 |
| 4 | 195 |
| 5 | 1521 |
| 6 | 16713 |
| 7 | 179425 |
| 8 | 2432139 |
| 9 | 33902149 |
| 10 | 546239793 |
| 11 | 9158893173 |
| 12 | 173742256251 |
| 13 | 3402217292137 |
| 14 | 73413011744985 |
| 15 | 1653326843775193 |
| 16 | 40118677865954475 |
| 17 | 1014971456865241197 |
| 18 | 27429061245764539521 |
| 19 | 770776923753566642365 |
| 20 | 22928146838491708702395 |
[1,1,5,25,195,1521,16713,179425,2432139,33902149, 546239793,9158893173,173742256251,3402217292137, 73413011744985,1653326843775193,40118677865954475, 1014971456865241197,27429061245764539521, 770776923753566642365,22928146838491708702395] |