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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 4 |
| 2 | 12 |
| 3 | 32 |
| 4 | 88 |
| 5 | 240 |
| 6 | 652 |
| 7 | 1744 |
| 8 | 4616 |
| 9 | 12208 |
| 10 | 32328 |
| 11 | 85408 |
| 12 | 224640 |
| 13 | 589024 |
| 14 | 1542944 |
| 15 | 4039256 |
| 16 | 10560552 |
| 17 | 27567488 |
| 18 | 71878068 |
| 19 | 187262944 |
| 20 | 487526944 |
| 21 | 1268269160 |
| 22 | 3296832292 |
| 23 | 8564411120 |
| 24 | 22235825104 |
| 25 | 57701041072 |
| 26 | 149657337872 |
| 27 | 387978891176 |
| 28 | 1005378745536 |
| 29 | 2604222063144 |
| 30 | 6743181213712 |
| 31 | 17454178002264 |
[1,4,12,32,88,240,652,1744,4616,12208,32328,85408, 224640,589024,1542944,4039256,10560552,27567488, 71878068,187262944,487526944,1268269160, 3296832292,8564411120,22235825104,57701041072, 149657337872,387978891176,1005378745536, 2604222063144,6743181213712,17454178002264] |