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| n | a(n) |
|---|---|
| 5 | 1 |
| 6 | 11 |
| 7 | 77 |
| 8 | 440 |
| 9 | 2244 |
| 10 | 10659 |
| 11 | 48279 |
| 12 | 211508 |
| 13 | 904475 |
| 14 | 3798795 |
| 15 | 15737865 |
| 16 | 64512240 |
| 17 | 262256280 |
| 18 | 1059111900 |
| 19 | 4254603804 |
| 20 | 17018415216 |
| 21 | 67837293986 |
| 22 | 269638992062 |
| 23 | 1069258071970 |
| 24 | 4232010895376 |
| 25 | 16723268860760 |
| 26 | 65997186039785 |
| 27 | 260170725132045 |
| 28 | 1024713341952300 |
[1,11,77,440,2244,10659,48279,211508,904475, 3798795,15737865,64512240,262256280,1059111900, 4254603804,17018415216,67837293986,269638992062, 1069258071970,4232010895376,16723268860760, 65997186039785,260170725132045,1024713341952300] |