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| n | a(n) |
|---|---|
| 9 | 1 |
| 10 | 10 |
| 11 | 100 |
| 12 | 760 |
| 13 | 5656 |
| 14 | 38416 |
| 15 | 257376 |
| 16 | 1660416 |
| 17 | 10640692 |
| 18 | 67100072 |
| 19 | 422374352 |
| 20 | 2643349180 |
| 21 | 16566306380 |
| 22 | 103786892840 |
| 23 | 652502735152 |
| 24 | 4113403313016 |
| 25 | 26057914447911 |
| 26 | 165824119892086 |
| 27 | 1061381766546172 |
| 28 | 6832087071296824 |
| 29 | 44260892997918920 |
| 30 | 288574772339715376 |
[1,10,100,760,5656,38416,257376,1660416,10640692, 67100072,422374352,2643349180,16566306380, 103786892840,652502735152,4113403313016, 26057914447911,165824119892086,1061381766546172, 6832087071296824,44260892997918920, 288574772339715376] |