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| n | a(n) |
|---|---|
| 1 | 16 |
| 2 | 21 |
| 3 | 58 |
| 4 | 153 |
| 5 | 445 |
| 6 | 1595 |
| 7 | 4772 |
| 8 | 15249 |
| 9 | 49634 |
| 10 | 166329 |
| 11 | 547264 |
| 12 | 1812790 |
| 13 | 6026255 |
| 14 | 20329381 |
| 15 | 68337634 |
| 16 | 228989976 |
| 17 | 768581607 |
| 18 | 2595937574 |
| 19 | 8761489896 |
| 20 | 29487968631 |
| 21 | 99305798186 |
| 22 | 335393857959 |
| 23 | 1132559861889 |
| 24 | 3818247323820 |
| 25 | 12874857356305 |
[16,21,58,153,445,1595,4772,15249,49634,166329, 547264,1812790,6026255,20329381,68337634, 228989976,768581607,2595937574,8761489896, 29487968631,99305798186,335393857959, 1132559861889,3818247323820,12874857356305] |