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| n | a(n) |
|---|---|
| 1 | 27 |
| 2 | 54 |
| 3 | 246 |
| 4 | 912 |
| 5 | 3612 |
| 6 | 13992 |
| 7 | 54600 |
| 8 | 212544 |
| 9 | 828048 |
| 10 | 3225120 |
| 11 | 12562464 |
| 12 | 48931776 |
| 13 | 190594944 |
| 14 | 742387008 |
| 15 | 2891677248 |
| 16 | 11263389888 |
| 17 | 43872104640 |
| 18 | 170886518976 |
| 19 | 665621195712 |
| 20 | 2592665453760 |
| 21 | 10098708106176 |
| 22 | 39335543742144 |
[27,54,246,912,3612,13992,54600,212544,828048, 3225120,12562464,48931776,190594944,742387008, 2891677248,11263389888,43872104640,170886518976, 665621195712,2592665453760,10098708106176, 39335543742144] |