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| n | a(n) |
|---|---|
| 3 | 0 |
| 4 | 2 |
| 5 | 2 |
| 6 | 3 |
| 7 | 9 |
| 8 | 15 |
| 9 | 34 |
| 10 | 94 |
| 11 | 209 |
| 12 | 504 |
| 13 | 1306 |
| 14 | 3073 |
| 15 | 7654 |
| 16 | 20149 |
| 17 | 50226 |
| 18 | 130772 |
| 19 | 338518 |
| 20 | 867558 |
| 21 | 2257485 |
| 22 | 5870934 |
| 23 | 15278349 |
| 24 | 40053657 |
| 25 | 105184694 |
| 26 | 276937693 |
| 27 | 732156972 |
| 28 | 1938948436 |
| 29 | 5148099462 |
| 30 | 13701809925 |
| 31 | 36532372370 |
[0,2,2,3,9,15,34,94,209,504,1306,3073,7654,20149, 50226,130772,338518,867558,2257485,5870934, 15278349,40053657,105184694,276937693,732156972, 1938948436,5148099462,13701809925,36532372370] |