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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 6 |
| 3 | 15 |
| 4 | 36 |
| 5 | 77 |
| 6 | 162 |
| 7 | 327 |
| 8 | 648 |
| 9 | 1262 |
| 10 | 2430 |
| 11 | 4629 |
| 12 | 8748 |
| 13 | 16414 |
| 14 | 30618 |
| 15 | 56819 |
| 16 | 104976 |
| 17 | 193187 |
| 18 | 354294 |
| 19 | 647747 |
| 20 | 1180980 |
| 21 | 2147793 |
| 22 | 3897234 |
| 23 | 7057034 |
| 24 | 12754584 |
| 25 | 23012070 |
| 26 | 41452398 |
| 27 | 74559107 |
| 28 | 133923132 |
| 29 | 240246014 |
| 30 | 430467210 |
| 31 | 770444114 |
| 32 | 1377495072 |
[1,6,15,36,77,162,327,648,1262,2430,4629,8748, 16414,30618,56819,104976,193187,354294,647747, 1180980,2147793,3897234,7057034,12754584,23012070, 41452398,74559107,133923132,240246014,430467210, 770444114,1377495072] |