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| n | a(n) |
|---|---|
| 1 | 2 |
| 2 | 13 |
| 3 | 19 |
| 4 | 30 |
| 5 | 53 |
| 6 | 90 |
| 7 | 145 |
| 8 | 244 |
| 9 | 406 |
| 10 | 771 |
| 11 | 1396 |
| 12 | 2472 |
| 13 | 4358 |
| 14 | 7688 |
| 15 | 13953 |
| 16 | 25626 |
| 17 | 46458 |
| 18 | 83576 |
| 19 | 150333 |
| 20 | 271566 |
| 21 | 494639 |
| 22 | 900920 |
| 23 | 1633015 |
| 24 | 2955455 |
| 25 | 5353266 |
| 26 | 9717165 |
| 27 | 17670119 |
| 28 | 32099391 |
| 29 | 58228907 |
| 30 | 105619960 |
| 31 | 191684445 |
| 32 | 348131289 |
| 33 | 632389497 |
[2,13,19,30,53,90,145,244,406,771,1396,2472,4358, 7688,13953,25626,46458,83576,150333,271566,494639, 900920,1633015,2955455,5353266,9717165,17670119, 32099391,58228907,105619960,191684445,348131289, 632389497] |