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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 2 |
| 2 | 5 |
| 3 | 14 |
| 4 | 38 |
| 5 | 102 |
| 6 | 273 |
| 7 | 731 |
| 8 | 1958 |
| 9 | 5245 |
| 10 | 14050 |
| 11 | 37636 |
| 12 | 100816 |
| 13 | 270057 |
| 14 | 723405 |
| 15 | 1937794 |
| 16 | 5190793 |
| 17 | 13904642 |
| 18 | 37246538 |
| 19 | 99772766 |
| 20 | 267262553 |
| 21 | 715919535 |
| 22 | 1917742590 |
| 23 | 5137081001 |
| 24 | 13760762966 |
| 25 | 36861127432 |
| 26 | 98740361920 |
| 27 | 264497039329 |
[1,2,5,14,38,102,273,731,1958,5245,14050,37636, 100816,270057,723405,1937794,5190793,13904642, 37246538,99772766,267262553,715919535,1917742590, 5137081001,13760762966,36861127432,98740361920, 264497039329] |