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| n | a(n) |
|---|---|
| 1 | 2 |
| 2 | 4 |
| 3 | 14 |
| 4 | 28 |
| 5 | 94 |
| 6 | 284 |
| 7 | 752 |
| 8 | 2244 |
| 9 | 6532 |
| 10 | 18472 |
| 11 | 53680 |
| 12 | 155040 |
| 13 | 445000 |
| 14 | 1285184 |
| 15 | 3706032 |
| 16 | 10672592 |
| 17 | 30778032 |
| 18 | 88725600 |
| 19 | 255701024 |
| 20 | 737147264 |
| 21 | 2124889120 |
| 22 | 6124798656 |
| 23 | 17655444096 |
| 24 | 50892739392 |
| 25 | 146699089600 |
| 26 | 422869223040 |
[2,4,14,28,94,284,752,2244,6532,18472,53680, 155040,445000,1285184,3706032,10672592,30778032, 88725600,255701024,737147264,2124889120, 6124798656,17655444096,50892739392,146699089600, 422869223040] |