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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 3 |
| 3 | 4 |
| 4 | 15 |
| 5 | 31 |
| 6 | 72 |
| 7 | 176 |
| 8 | 327 |
| 9 | 751 |
| 10 | 2063 |
| 11 | 5138 |
| 12 | 12708 |
| 13 | 30993 |
| 14 | 75386 |
| 15 | 182644 |
| 16 | 433255 |
| 17 | 1004854 |
| 18 | 2279349 |
| 19 | 5115960 |
| 20 | 11580835 |
| 21 | 26533616 |
| 22 | 62024966 |
| 23 | 149683357 |
| 24 | 373141332 |
| 25 | 957942931 |
| 26 | 2516465279 |
| 27 | 6694846987 |
| 28 | 17883365774 |
| 29 | 47644695777 |
| 30 | 125952933062 |
| 31 | 329364348277 |
[1,3,4,15,31,72,176,327,751,2063,5138,12708,30993, 75386,182644,433255,1004854,2279349,5115960, 11580835,26533616,62024966,149683357,373141332, 957942931,2516465279,6694846987,17883365774, 47644695777,125952933062,329364348277] |