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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 7 |
| 3 | 9 |
| 4 | 31 |
| 5 | 53 |
| 6 | 141 |
| 7 | 380 |
| 8 | 1010 |
| 9 | 2152 |
| 10 | 5014 |
| 11 | 14018 |
| 12 | 35542 |
| 13 | 78385 |
| 14 | 188789 |
| 15 | 503051 |
| 16 | 1241939 |
| 17 | 2859687 |
| 18 | 6957672 |
| 19 | 17863397 |
| 20 | 43991846 |
| 21 | 103888178 |
| 22 | 253531752 |
| 23 | 640390692 |
| 24 | 1575397895 |
| 25 | 3777406958 |
| 26 | 9259136398 |
| 27 | 23167497450 |
| 28 | 57008137128 |
| 29 | 138220165963 |
[1,7,9,31,53,141,380,1010,2152,5014,14018,35542, 78385,188789,503051,1241939,2859687,6957672, 17863397,43991846,103888178,253531752,640390692, 1575397895,3777406958,9259136398,23167497450, 57008137128,138220165963] |