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| n | a(n) |
|---|---|
| 5 | 1 |
| 6 | 2 |
| 7 | 7 |
| 8 | 23 |
| 9 | 77 |
| 10 | 256 |
| 11 | 861 |
| 12 | 2897 |
| 13 | 9800 |
| 14 | 33232 |
| 15 | 113012 |
| 16 | 385165 |
| 17 | 1315434 |
| 18 | 4500398 |
| 19 | 15421463 |
| 20 | 52919299 |
| 21 | 181826880 |
| 22 | 625467087 |
| 23 | 2153816295 |
| 24 | 7423887771 |
| 25 | 25611710370 |
| 26 | 88430103927 |
| 27 | 305555059139 |
| 28 | 1056532822348 |
| 29 | 3655607694207 |
| 30 | 12656112780583 |
| 31 | 43841784746311 |
[1,2,7,23,77,256,861,2897,9800,33232,113012, 385165,1315434,4500398,15421463,52919299, 181826880,625467087,2153816295,7423887771, 25611710370,88430103927,305555059139, 1056532822348,3655607694207,12656112780583, 43841784746311] |