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| n | a(n) |
|---|---|
| 1 | 2 |
| 2 | 6 |
| 3 | 9 |
| 4 | 18 |
| 5 | 54 |
| 6 | 99 |
| 7 | 216 |
| 8 | 512 |
| 9 | 1079 |
| 10 | 2352 |
| 11 | 5225 |
| 12 | 11383 |
| 13 | 24991 |
| 14 | 54814 |
| 15 | 120126 |
| 16 | 263554 |
| 17 | 577644 |
| 18 | 1266485 |
| 19 | 2777763 |
| 20 | 6089610 |
| 21 | 13352283 |
| 22 | 29278137 |
| 23 | 64194490 |
| 24 | 140755609 |
| 25 | 308628427 |
| 26 | 676706615 |
| 27 | 1483775356 |
| 28 | 3253378624 |
| 29 | 7133479611 |
| 30 | 15641147936 |
| 31 | 34295353874 |
| 32 | 75197276962 |
[2,6,9,18,54,99,216,512,1079,2352,5225,11383, 24991,54814,120126,263554,577644,1266485,2777763, 6089610,13352283,29278137,64194490,140755609, 308628427,676706615,1483775356,3253378624, 7133479611,15641147936,34295353874,75197276962] |