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| n | a(n) |
|---|---|
| 1 | 13 |
| 2 | 49 |
| 3 | 53 |
| 4 | 140 |
| 5 | 320 |
| 6 | 651 |
| 7 | 1321 |
| 8 | 2673 |
| 9 | 5293 |
| 10 | 10668 |
| 11 | 21704 |
| 12 | 43407 |
| 13 | 86685 |
| 14 | 174463 |
| 15 | 350613 |
| 16 | 704014 |
| 17 | 1416102 |
| 18 | 2846067 |
| 19 | 5718303 |
| 20 | 11503925 |
| 21 | 23146779 |
| 22 | 46553188 |
| 23 | 93651586 |
| 24 | 188449221 |
| 25 | 379193323 |
| 26 | 763054735 |
| 27 | 1535660833 |
| 28 | 3090522976 |
| 29 | 6219809542 |
[13,49,53,140,320,651,1321,2673,5293,10668,21704, 43407,86685,174463,350613,704014,1416102,2846067, 5718303,11503925,23146779,46553188,93651586, 188449221,379193323,763054735,1535660833, 3090522976,6219809542] |