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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 1 |
| 2 | 2 |
| 3 | 5 |
| 4 | 11 |
| 5 | 32 |
| 6 | 87 |
| 7 | 248 |
| 8 | 764 |
| 9 | 2263 |
| 10 | 7125 |
| 11 | 22502 |
| 12 | 71308 |
| 13 | 232915 |
| 14 | 756571 |
| 15 | 2496821 |
| 16 | 8313892 |
| 17 | 27728911 |
| 18 | 93585460 |
| 19 | 316624455 |
| 20 | 1077272837 |
| 21 | 3687696937 |
| 22 | 12654416060 |
| 23 | 43655883878 |
| 24 | 151090181445 |
| 25 | 524542100001 |
| 26 | 1827895867960 |
| 27 | 6385078233779 |
| 28 | 22370743311415 |
| 29 | 78580314467710 |
| 30 | 276639299185638 |
| 31 | 976285257901368 |
[1,1,2,5,11,32,87,248,764,2263,7125,22502,71308, 232915,756571,2496821,8313892,27728911,93585460, 316624455,1077272837,3687696937,12654416060, 43655883878,151090181445,524542100001, 1827895867960,6385078233779,22370743311415, 78580314467710,276639299185638,976285257901368] |