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| n | a(n) |
|---|---|
| 0 | 11 |
| 1 | 90 |
| 2 | 372 |
| 3 | 1512 |
| 4 | 6096 |
| 5 | 24480 |
| 6 | 98112 |
| 7 | 392832 |
| 8 | 1572096 |
| 9 | 6289920 |
| 10 | 25162752 |
| 11 | 100657152 |
| 12 | 402640896 |
| 13 | 1610588160 |
| 14 | 6442401792 |
| 15 | 25769705472 |
| 16 | 103079018496 |
| 17 | 412316467200 |
| 18 | 1649266655232 |
| 19 | 6597068193792 |
| 20 | 26388275920896 |
[11,90,372,1512,6096,24480,98112,392832,1572096, 6289920,25162752,100657152,402640896,1610588160, 6442401792,25769705472,103079018496,412316467200, 1649266655232,6597068193792,26388275920896] |