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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 1 |
| 2 | 1 |
| 3 | 1 |
| 4 | 1 |
| 5 | 1 |
| 6 | 1 |
| 7 | 211 |
| 8 | 1681 |
| 9 | 7561 |
| 10 | 25201 |
| 11 | 69301 |
| 12 | 166321 |
| 13 | 360361 |
| 14 | 990991 |
| 15 | 5405401 |
| 16 | 34834801 |
| 17 | 187867681 |
| 18 | 833709241 |
| 19 | 3153281041 |
| 20 | 10491944401 |
| 21 | 31945216801 |
| 22 | 97323704941 |
| 23 | 345845431471 |
| 24 | 1529597398561 |
| 25 | 7451402805001 |
| 26 | 35092646589001 |
| 27 | 151591791651301 |
[1,1,1,1,1,1,1,211,1681,7561,25201,69301,166321, 360361,990991,5405401,34834801,187867681, 833709241,3153281041,10491944401,31945216801, 97323704941,345845431471,1529597398561, 7451402805001,35092646589001,151591791651301] |