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| n | a(n) |
|---|---|
| 1 | 6 |
| 2 | 36 |
| 3 | 102 |
| 4 | 283 |
| 5 | 699 |
| 6 | 1526 |
| 7 | 3355 |
| 8 | 6888 |
| 9 | 13954 |
| 10 | 27816 |
| 11 | 54211 |
| 12 | 105147 |
| 13 | 201340 |
| 14 | 382799 |
| 15 | 723838 |
| 16 | 1359688 |
| 17 | 2544322 |
| 18 | 4740623 |
| 19 | 8801291 |
| 20 | 16292518 |
| 21 | 30071783 |
| 22 | 55371672 |
| 23 | 101727342 |
| 24 | 186506700 |
| 25 | 341316455 |
| 26 | 623552411 |
| 27 | 1137394900 |
| 28 | 2071676507 |
[6,36,102,283,699,1526,3355,6888,13954,27816, 54211,105147,201340,382799,723838,1359688,2544322, 4740623,8801291,16292518,30071783,55371672, 101727342,186506700,341316455,623552411, 1137394900,2071676507] |