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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 13 |
| 3 | 21 |
| 4 | 26 |
| 5 | 70 |
| 6 | 139 |
| 7 | 287 |
| 8 | 625 |
| 9 | 1484 |
| 10 | 3197 |
| 11 | 7321 |
| 12 | 17097 |
| 13 | 38454 |
| 14 | 89084 |
| 15 | 206798 |
| 16 | 474945 |
| 17 | 1101200 |
| 18 | 2553611 |
| 19 | 5907111 |
| 20 | 13701807 |
| 21 | 31776804 |
| 22 | 73676950 |
| 23 | 170939314 |
| 24 | 396615800 |
| 25 | 920204959 |
| 26 | 2135416683 |
| 27 | 4955594995 |
| 28 | 11500595479 |
| 29 | 26691033523 |
[1,13,21,26,70,139,287,625,1484,3197,7321,17097, 38454,89084,206798,474945,1101200,2553611,5907111, 13701807,31776804,73676950,170939314,396615800, 920204959,2135416683,4955594995,11500595479, 26691033523] |