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| n | a(n) |
|---|---|
| 0 | 4 |
| 1 | 10 |
| 2 | 24 |
| 3 | 55 |
| 4 | 120 |
| 5 | 254 |
| 6 | 524 |
| 7 | 1059 |
| 8 | 2104 |
| 9 | 4120 |
| 10 | 7968 |
| 11 | 15244 |
| 12 | 28888 |
| 13 | 54284 |
| 14 | 101240 |
| 15 | 187537 |
| 16 | 345268 |
| 17 | 632122 |
| 18 | 1151408 |
| 19 | 2087485 |
| 20 | 3768280 |
| 21 | 6775322 |
| 22 | 12136940 |
| 23 | 21666712 |
| 24 | 38555100 |
| 25 | 68401582 |
| 26 | 121011800 |
| 27 | 213521067 |
| 28 | 375813760 |
| 29 | 659910710 |
| 30 | 1156204452 |
| 31 | 2021495767 |
[4,10,24,55,120,254,524,1059,2104,4120,7968,15244, 28888,54284,101240,187537,345268,632122,1151408, 2087485,3768280,6775322,12136940,21666712, 38555100,68401582,121011800,213521067,375813760, 659910710,1156204452,2021495767] |