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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 8 |
| 3 | 24 |
| 4 | 82 |
| 5 | 316 |
| 6 | 1182 |
| 7 | 4560 |
| 8 | 17508 |
| 9 | 67310 |
| 10 | 259398 |
| 11 | 999368 |
| 12 | 3851828 |
| 13 | 14846772 |
| 14 | 57226834 |
| 15 | 220589358 |
| 16 | 850295818 |
| 17 | 3277615080 |
| 18 | 12634174925 |
| 19 | 48700783032 |
| 20 | 187726368115 |
| 21 | 723626846696 |
| 22 | 2789356995974 |
| 23 | 10752106442068 |
| 24 | 41446037382414 |
[1,8,24,82,316,1182,4560,17508,67310,259398, 999368,3851828,14846772,57226834,220589358, 850295818,3277615080,12634174925,48700783032, 187726368115,723626846696,2789356995974, 10752106442068,41446037382414] |