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| n | a(n) |
|---|---|
| 1 | 2 |
| 2 | 6 |
| 3 | 10 |
| 4 | 23 |
| 5 | 42 |
| 6 | 98 |
| 7 | 178 |
| 8 | 415 |
| 9 | 754 |
| 10 | 1758 |
| 11 | 3194 |
| 12 | 7447 |
| 13 | 13530 |
| 14 | 31546 |
| 15 | 57314 |
| 16 | 133631 |
| 17 | 242786 |
| 18 | 566070 |
| 19 | 1028458 |
| 20 | 2397911 |
| 21 | 4356618 |
| 22 | 10157714 |
| 23 | 18454930 |
| 24 | 43028767 |
| 25 | 78176338 |
| 26 | 182272782 |
| 27 | 331160282 |
| 28 | 772119895 |
| 29 | 1402817466 |
| 30 | 3270752362 |
[2,6,10,23,42,98,178,415,754,1758,3194,7447,13530, 31546,57314,133631,242786,566070,1028458,2397911, 4356618,10157714,18454930,43028767,78176338, 182272782,331160282,772119895,1402817466, 3270752362] |