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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 12 |
| 2 | 132 |
| 3 | 1452 |
| 4 | 15972 |
| 5 | 175692 |
| 6 | 1932612 |
| 7 | 21258732 |
| 8 | 233846052 |
| 9 | 2572306572 |
| 10 | 28295372292 |
| 11 | 311249095212 |
| 12 | 3423740047332 |
| 13 | 37661140520652 |
| 14 | 414272545727106 |
| 15 | 4556998002997440 |
| 16 | 50126978032963920 |
| 17 | 551396758362516000 |
[1,12,132,1452,15972,175692,1932612,21258732, 233846052,2572306572,28295372292,311249095212, 3423740047332,37661140520652,414272545727106, 4556998002997440,50126978032963920, 551396758362516000] |