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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 7 |
| 3 | 5 |
| 4 | 15 |
| 5 | 21 |
| 6 | 57 |
| 7 | 121 |
| 8 | 289 |
| 9 | 747 |
| 10 | 1901 |
| 11 | 5017 |
| 12 | 13531 |
| 13 | 36501 |
| 14 | 99555 |
| 15 | 272873 |
| 16 | 748887 |
| 17 | 2061111 |
| 18 | 5679261 |
| 19 | 15657685 |
| 20 | 43198325 |
| 21 | 119216101 |
| 22 | 329067269 |
| 23 | 908467521 |
| 24 | 2508239639 |
| 25 | 6925531875 |
| 26 | 19123005315 |
| 27 | 52804249441 |
| 28 | 145810426239 |
| 29 | 402636515557 |
[1,7,5,15,21,57,121,289,747,1901,5017,13531,36501, 99555,272873,748887,2061111,5679261,15657685, 43198325,119216101,329067269,908467521,2508239639, 6925531875,19123005315,52804249441,145810426239, 402636515557] |