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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 1 |
| 2 | 2 |
| 3 | 5 |
| 4 | 15 |
| 5 | 38 |
| 6 | 126 |
| 7 | 403 |
| 8 | 1279 |
| 9 | 4376 |
| 10 | 15361 |
| 11 | 52102 |
| 12 | 188609 |
| 13 | 680752 |
| 14 | 2450641 |
| 15 | 9089379 |
| 16 | 33719262 |
| 17 | 125430770 |
| 18 | 475968218 |
| 19 | 1796731739 |
| 20 | 6849544648 |
| 21 | 26396870678 |
| 22 | 101253870085 |
| 23 | 392467382251 |
| 24 | 1531000530315 |
| 25 | 5952481787141 |
| 26 | 23368070361558 |
| 27 | 91997443972187 |
| 28 | 361899755511914 |
| 29 | 1434849012341938 |
| 30 | 5692008006992570 |
[1,1,2,5,15,38,126,403,1279,4376,15361,52102, 188609,680752,2450641,9089379,33719262,125430770, 475968218,1796731739,6849544648,26396870678, 101253870085,392467382251,1531000530315, 5952481787141,23368070361558,91997443972187, 361899755511914,1434849012341938,5692008006992570] |