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| n | a(n) |
|---|---|
| 1 | 16 |
| 2 | 132 |
| 3 | 494 |
| 4 | 1498 |
| 5 | 3936 |
| 6 | 9630 |
| 7 | 22656 |
| 8 | 52110 |
| 9 | 118182 |
| 10 | 265458 |
| 11 | 591924 |
| 12 | 1311966 |
| 13 | 2892738 |
| 14 | 6348402 |
| 15 | 13873152 |
| 16 | 30199422 |
| 17 | 65504766 |
| 18 | 141618834 |
| 19 | 305248332 |
| 20 | 656098110 |
[16,132,494,1498,3936,9630,22656,52110,118182, 265458,591924,1311966,2892738,6348402,13873152, 30199422,65504766,141618834,305248332,656098110] |