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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 1 |
| 2 | 1 |
| 3 | 3 |
| 4 | 7 |
| 5 | 15 |
| 6 | 45 |
| 7 | 123 |
| 8 | 341 |
| 9 | 1055 |
| 10 | 3143 |
| 11 | 9687 |
| 12 | 30859 |
| 13 | 97483 |
| 14 | 315861 |
| 15 | 1033493 |
| 16 | 3395089 |
| 17 | 11316469 |
| 18 | 37893747 |
| 19 | 127757627 |
| 20 | 434147079 |
| 21 | 1481301463 |
| 22 | 5084504675 |
| 23 | 17536498671 |
| 24 | 60720379293 |
| 25 | 211194514011 |
| 26 | 737154897245 |
| 27 | 2581907565225 |
| 28 | 9073734424809 |
| 29 | 31980512271541 |
| 30 | 113042537052043 |
| 31 | 400634089054315 |
| 32 | 1423370290109371 |
[1,1,1,3,7,15,45,123,341,1055,3143,9687,30859, 97483,315861,1033493,3395089,11316469,37893747, 127757627,434147079,1481301463,5084504675, 17536498671,60720379293,211194514011,737154897245, 2581907565225,9073734424809,31980512271541, 113042537052043,400634089054315,1423370290109371] |