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| n | a(n) |
|---|---|
| 1 | 2 |
| 2 | 14 |
| 3 | 132 |
| 4 | 484 |
| 5 | 1734 |
| 6 | 4386 |
| 7 | 10376 |
| 8 | 20840 |
| 9 | 39690 |
| 10 | 68950 |
| 11 | 115212 |
| 12 | 181644 |
| 13 | 278222 |
| 14 | 409514 |
| 15 | 589584 |
| 16 | 824656 |
| 17 | 1133586 |
| 18 | 1524510 |
| 19 | 2021780 |
| 20 | 2635700 |
| 21 | 3396822 |
| 22 | 4317874 |
| 23 | 5436312 |
| 24 | 6767544 |
| 25 | 8356634 |
| 26 | 10221926 |
| 27 | 12416796 |
| 28 | 14962780 |
| 29 | 17922270 |
| 30 | 21320250 |
[2,14,132,484,1734,4386,10376,20840,39690,68950, 115212,181644,278222,409514,589584,824656,1133586, 1524510,2021780,2635700,3396822,4317874,5436312, 6767544,8356634,10221926,12416796,14962780, 17922270,21320250] |