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| n | a(n) |
|---|---|
| 1 | 256 |
| 2 | 656 |
| 3 | 1728 |
| 4 | 4820 |
| 5 | 13624 |
| 6 | 39884 |
| 7 | 117488 |
| 8 | 354588 |
| 9 | 1072888 |
| 10 | 3306172 |
| 11 | 10189840 |
| 12 | 31866620 |
| 13 | 99499864 |
| 14 | 314460540 |
| 15 | 990959472 |
| 16 | 3155587516 |
| 17 | 10009630136 |
| 18 | 32048121852 |
| 19 | 102135500880 |
| 20 | 328299662204 |
| 21 | 1049814687640 |
| 22 | 3384204174332 |
[256,656,1728,4820,13624,39884,117488,354588, 1072888,3306172,10189840,31866620,99499864, 314460540,990959472,3155587516,10009630136, 32048121852,102135500880,328299662204, 1049814687640,3384204174332] |