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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 2 |
| 2 | 7 |
| 3 | 27 |
| 4 | 115 |
| 5 | 501 |
| 6 | 2266 |
| 7 | 10414 |
| 8 | 48673 |
| 9 | 229899 |
| 10 | 1095774 |
| 11 | 5259354 |
| 12 | 25385793 |
| 13 | 123107126 |
| 14 | 599282303 |
| 15 | 2926781377 |
| 16 | 14332693879 |
| 17 | 70352155139 |
| 18 | 346012928712 |
| 19 | 1704732039933 |
| 20 | 8411438735489 |
| 21 | 41557786740897 |
| 22 | 205557391371019 |
| 23 | 1017777949837131 |
| 24 | 5043845141082382 |
| 25 | 25015871533786025 |
| 26 | 124158696941193602 |
[1,2,7,27,115,501,2266,10414,48673,229899,1095774, 5259354,25385793,123107126,599282303,2926781377, 14332693879,70352155139,346012928712, 1704732039933,8411438735489,41557786740897, 205557391371019,1017777949837131,5043845141082382, 25015871533786025,124158696941193602] |