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| n | a(n) |
|---|---|
| 2 | 0 |
| 3 | 0 |
| 4 | 1 |
| 5 | 1 |
| 6 | 3 |
| 7 | 5 |
| 8 | 12 |
| 9 | 27 |
| 10 | 62 |
| 11 | 149 |
| 12 | 371 |
| 13 | 952 |
| 14 | 2513 |
| 15 | 6807 |
| 16 | 18873 |
| 17 | 53472 |
| 18 | 154554 |
| 19 | 455076 |
| 20 | 1363287 |
| 21 | 4150560 |
| 22 | 12829558 |
| 23 | 40227005 |
| 24 | 127843589 |
| 25 | 411512640 |
| 26 | 1340747909 |
| 27 | 4418886387 |
| 28 | 14724633149 |
| 29 | 49582195801 |
| 30 | 168638834537 |
| 31 | 579103599979 |
[0,0,1,1,3,5,12,27,62,149,371,952,2513,6807,18873, 53472,154554,455076,1363287,4150560,12829558, 40227005,127843589,411512640,1340747909, 4418886387,14724633149,49582195801,168638834537, 579103599979] |