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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 1 |
| 2 | 2 |
| 3 | 8 |
| 4 | 29 |
| 5 | 105 |
| 6 | 414 |
| 7 | 1695 |
| 8 | 7046 |
| 9 | 29853 |
| 10 | 128644 |
| 11 | 561262 |
| 12 | 2474142 |
| 13 | 11006108 |
| 14 | 49343508 |
| 15 | 222715440 |
| 16 | 1011217425 |
| 17 | 4615519083 |
| 18 | 21165513228 |
| 19 | 97467424198 |
| 20 | 450541090701 |
| 21 | 2089777230606 |
| 22 | 9723511785608 |
| 23 | 45371996501895 |
| 24 | 212271904284993 |
| 25 | 995513843930049 |
| 26 | 4679212044797252 |
[1,1,2,8,29,105,414,1695,7046,29853,128644,561262, 2474142,11006108,49343508,222715440,1011217425, 4615519083,21165513228,97467424198,450541090701, 2089777230606,9723511785608,45371996501895, 212271904284993,995513843930049,4679212044797252] |