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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 2 |
| 2 | 14 |
| 3 | 48 |
| 4 | 236 |
| 5 | 952 |
| 6 | 4264 |
| 7 | 18048 |
| 8 | 78736 |
| 9 | 337952 |
| 10 | 1463264 |
| 11 | 6306048 |
| 12 | 27244736 |
| 13 | 117549952 |
| 14 | 507547264 |
| 15 | 2190594048 |
| 16 | 9456660736 |
| 17 | 40819261952 |
| 18 | 176205131264 |
| 19 | 760602882048 |
| 20 | 3283257076736 |
| 21 | 14172542973952 |
| 22 | 61177656715264 |
| 23 | 264080743170048 |
| 24 | 1139938053492736 |
| 25 | 4920683538685952 |
[1,2,14,48,236,952,4264,18048,78736,337952, 1463264,6306048,27244736,117549952,507547264, 2190594048,9456660736,40819261952,176205131264, 760602882048,3283257076736,14172542973952, 61177656715264,264080743170048,1139938053492736, 4920683538685952] |