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| n | a(n) |
|---|---|
| 1 | 12 |
| 2 | 36 |
| 3 | 138 |
| 4 | 270 |
| 5 | 546 |
| 6 | 4800 |
| 7 | 7560 |
| 8 | 12840 |
| 9 | 14700 |
| 10 | 358200 |
| 11 | 678480 |
| 12 | 16139970 |
| 13 | 22934100 |
| 14 | 55058580 |
| 15 | 59553720 |
| 16 | 74371320 |
| 17 | 113068380 |
| 18 | 116605860 |
| 19 | 242699310 |
| 20 | 997521210 |
| 21 | 1592680320 |
| 22 | 1652749200 |
| 23 | 3190927740 |
| 24 | 5088964800 |
| 25 | 6974736756 |
| 26 | 9214178820 |
[12,36,138,270,546,4800,7560,12840,14700,358200, 678480,16139970,22934100,55058580,59553720, 74371320,113068380,116605860,242699310,997521210, 1592680320,1652749200,3190927740,5088964800, 6974736756,9214178820] |