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| n | a(n) |
|---|---|
| 1 | 0 |
| 2 | 5 |
| 3 | 4 |
| 4 | 46 |
| 5 | 151 |
| 6 | 543 |
| 7 | 2120 |
| 8 | 8155 |
| 9 | 30205 |
| 10 | 115292 |
| 11 | 437367 |
| 12 | 1652127 |
| 13 | 6259372 |
| 14 | 23720673 |
| 15 | 89793169 |
| 16 | 340068226 |
| 17 | 1288031893 |
| 18 | 4877697803 |
| 19 | 18472359472 |
| 20 | 69958934289 |
| 21 | 264942827367 |
| 22 | 1003373594916 |
| 23 | 3799932457113 |
| 24 | 14390883952121 |
| 25 | 54500311291862 |
[0,5,4,46,151,543,2120,8155,30205,115292,437367, 1652127,6259372,23720673,89793169,340068226, 1288031893,4877697803,18472359472,69958934289, 264942827367,1003373594916,3799932457113, 14390883952121,54500311291862] |