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| n | a(n) |
|---|---|
| 1 | 6 |
| 2 | 12 |
| 3 | 36 |
| 4 | 114 |
| 5 | 420 |
| 6 | 1584 |
| 7 | 6228 |
| 8 | 24930 |
| 9 | 101376 |
| 10 | 417504 |
| 11 | 1734876 |
| 12 | 7271238 |
| 13 | 30667068 |
| 14 | 130119672 |
| 15 | 554721564 |
| 16 | 2375331042 |
| 17 | 10209040920 |
| 18 | 44027206416 |
| 19 | 190434749196 |
| 20 | 825936571446 |
| 21 | 3590858184996 |
| 22 | 15646265986056 |
| 23 | 68311732725204 |
[6,12,36,114,420,1584,6228,24930,101376,417504, 1734876,7271238,30667068,130119672,554721564, 2375331042,10209040920,44027206416,190434749196, 825936571446,3590858184996,15646265986056, 68311732725204] |