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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 1 |
| 2 | 1 |
| 3 | 2 |
| 4 | 5 |
| 5 | 17 |
| 6 | 68 |
| 7 | 326 |
| 8 | 1780 |
| 9 | 11033 |
| 10 | 76028 |
| 11 | 578290 |
| 12 | 4803696 |
| 13 | 43297358 |
| 14 | 420639362 |
| 15 | 4382320595 |
| 16 | 48729809104 |
| 17 | 576039659209 |
| 18 | 7213070102518 |
| 19 | 95373808983223 |
| 20 | 1327842798808220 |
| 21 | 19416307366048221 |
| 22 | 297499363267839558 |
| 23 | 4766432683120731044 |
| 24 | 79699553284422816437 |
| 25 | 1388383661114307067780 |
| 26 | 25156549558328842669336 |
[1,1,1,2,5,17,68,326,1780,11033,76028,578290, 4803696,43297358,420639362,4382320595,48729809104, 576039659209,7213070102518,95373808983223, 1327842798808220,19416307366048221, 297499363267839558,4766432683120731044, 79699553284422816437,1388383661114307067780, 25156549558328842669336] |