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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 16 |
| 2 | 135 |
| 3 | 800 |
| 4 | 3739 |
| 5 | 14672 |
| 6 | 50252 |
| 7 | 154224 |
| 8 | 432174 |
| 9 | 1121456 |
| 10 | 2724183 |
| 11 | 6248128 |
| 12 | 13624922 |
| 13 | 28409312 |
| 14 | 56910017 |
| 15 | 109964720 |
| 16 | 205651975 |
| 17 | 373334400 |
| 18 | 659553555 |
| 19 | 1136450288 |
| 20 | 1913567669 |
| 21 | 3154109024 |
| 22 | 5096972454 |
| 23 | 8086166144 |
| 24 | 12609525259 |
[1,16,135,800,3739,14672,50252,154224,432174, 1121456,2724183,6248128,13624922,28409312, 56910017,109964720,205651975,373334400,659553555, 1136450288,1913567669,3154109024,5096972454, 8086166144,12609525259] |