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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 1 |
| 3 | 2 |
| 4 | 5 |
| 5 | 8 |
| 6 | 27 |
| 7 | 44 |
| 8 | 137 |
| 9 | 305 |
| 10 | 905 |
| 11 | 1466 |
| 12 | 7411 |
| 13 | 11986 |
| 14 | 33597 |
| 15 | 91007 |
| 16 | 322205 |
| 17 | 521306 |
| 18 | 2292156 |
| 19 | 3708875 |
| 20 | 15639101 |
| 21 | 40100349 |
| 22 | 106348943 |
| 23 | 172076807 |
| 24 | 1071988711 |
| 25 | 2129108426 |
| 26 | 5564227811 |
| 27 | 13812311521 |
| 28 | 53326260495 |
| 29 | 86283685147 |
| 30 | 492560346093 |
[1,1,2,5,8,27,44,137,305,905,1466,7411,11986, 33597,91007,322205,521306,2292156,3708875, 15639101,40100349,106348943,172076807,1071988711, 2129108426,5564227811,13812311521,53326260495, 86283685147,492560346093] |