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| n | a(n) |
|---|---|
| 1 | 3 |
| 2 | 30 |
| 3 | 144 |
| 4 | 588 |
| 5 | 2160 |
| 6 | 7440 |
| 7 | 24576 |
| 8 | 78912 |
| 9 | 248448 |
| 10 | 771456 |
| 11 | 2371968 |
| 12 | 7241856 |
| 13 | 21998976 |
| 14 | 66586752 |
| 15 | 201025920 |
| 16 | 605781120 |
| 17 | 1823094144 |
| 18 | 5481472128 |
| 19 | 16470172032 |
| 20 | 49464779904 |
| 21 | 148508372352 |
| 22 | 445764192384 |
| 23 | 1337792747904 |
[3,30,144,588,2160,7440,24576,78912,248448,771456, 2371968,7241856,21998976,66586752,201025920, 605781120,1823094144,5481472128,16470172032, 49464779904,148508372352,445764192384, 1337792747904] |