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| n | a(n) |
|---|---|
| 1 | 12 |
| 2 | 144 |
| 3 | 636 |
| 4 | 3560 |
| 5 | 18688 |
| 6 | 101036 |
| 7 | 541380 |
| 8 | 2906592 |
| 9 | 15585680 |
| 10 | 83611228 |
| 11 | 448508160 |
| 12 | 2406031628 |
| 13 | 12906861916 |
| 14 | 69237527840 |
| 15 | 371416568460 |
| 16 | 1992423747700 |
| 17 | 10688138114240 |
| 18 | 57335348257076 |
| 19 | 307569175706760 |
| 20 | 1649921069864080 |
[12,144,636,3560,18688,101036,541380,2906592, 15585680,83611228,448508160,2406031628, 12906861916,69237527840,371416568460, 1992423747700,10688138114240,57335348257076, 307569175706760,1649921069864080] |