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| n | a(n) |
|---|---|
| 1 | 6 |
| 2 | 36 |
| 3 | 696 |
| 4 | 3960 |
| 5 | 44092 |
| 6 | 245952 |
| 7 | 2148348 |
| 8 | 11909916 |
| 9 | 92914316 |
| 10 | 516123540 |
| 11 | 3754783282 |
| 12 | 20944422720 |
| 13 | 145858066580 |
| 14 | 819115053456 |
| 15 | 5532833258412 |
| 16 | 31237280045460 |
| 17 | 206640812099598 |
| 18 | 1173206191661712 |
[6,36,696,3960,44092,245952,2148348,11909916, 92914316,516123540,3754783282,20944422720, 145858066580,819115053456,5532833258412, 31237280045460,206640812099598,1173206191661712] |