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| n | a(n) |
|---|---|
| 3 | 0 |
| 4 | 1 |
| 5 | 3 |
| 6 | 6 |
| 7 | 19 |
| 8 | 33 |
| 9 | 55 |
| 10 | 143 |
| 11 | 373 |
| 12 | 625 |
| 13 | 1591 |
| 14 | 3352 |
| 15 | 7394 |
| 16 | 17417 |
| 17 | 40868 |
| 18 | 94739 |
| 19 | 242601 |
| 20 | 592513 |
| 21 | 1539546 |
| 22 | 3983209 |
| 23 | 10537005 |
| 24 | 27863927 |
| 25 | 74589746 |
| 26 | 198484953 |
| 27 | 531289122 |
| 28 | 1413431762 |
| 29 | 3765937102 |
| 30 | 9987163602 |
| 31 | 26495409644 |
[0,1,3,6,19,33,55,143,373,625,1591,3352,7394, 17417,40868,94739,242601,592513,1539546,3983209, 10537005,27863927,74589746,198484953,531289122, 1413431762,3765937102,9987163602,26495409644] |