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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 3 |
| 2 | 6 |
| 3 | 27 |
| 4 | 48 |
| 5 | 132 |
| 6 | 324 |
| 7 | 651 |
| 8 | 1491 |
| 9 | 3078 |
| 10 | 6447 |
| 11 | 12795 |
| 12 | 25839 |
| 13 | 50088 |
| 14 | 96099 |
| 15 | 184491 |
| 16 | 343920 |
| 17 | 640545 |
| 18 | 1173609 |
| 19 | 2138403 |
| 20 | 3850584 |
| 21 | 6882354 |
| 22 | 12186336 |
| 23 | 21423660 |
| 24 | 37421757 |
| 25 | 64816608 |
| 26 | 111637392 |
| 27 | 190976859 |
| 28 | 324868530 |
| 29 | 549265290 |
| 30 | 923904711 |
| 31 | 1545406077 |
| 32 | 2572326510 |
[1,3,6,27,48,132,324,651,1491,3078,6447,12795, 25839,50088,96099,184491,343920,640545,1173609, 2138403,3850584,6882354,12186336,21423660, 37421757,64816608,111637392,190976859,324868530, 549265290,923904711,1545406077,2572326510] |