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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 11 |
| 3 | 43 |
| 4 | 127 |
| 5 | 331 |
| 6 | 807 |
| 7 | 1891 |
| 8 | 4319 |
| 9 | 9691 |
| 10 | 21463 |
| 11 | 47059 |
| 12 | 102351 |
| 13 | 221131 |
| 14 | 475079 |
| 15 | 1015747 |
| 16 | 2162623 |
| 17 | 4587451 |
| 18 | 9699255 |
| 19 | 20447155 |
| 20 | 42991535 |
| 21 | 90177451 |
| 22 | 188743591 |
| 23 | 394264483 |
| 24 | 822083487 |
| 25 | 1711275931 |
| 26 | 3556769687 |
| 27 | 7381974931 |
[1,11,43,127,331,807,1891,4319,9691,21463,47059, 102351,221131,475079,1015747,2162623,4587451, 9699255,20447155,42991535,90177451,188743591, 394264483,822083487,1711275931,3556769687, 7381974931] |