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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 1 |
| 3 | 1 |
| 4 | 2 |
| 5 | 6 |
| 6 | 21 |
| 7 | 112 |
| 8 | 853 |
| 9 | 111 |
| 10 | 181 |
| 11 | 323 |
| 12 | 437 |
| 13 | 717 |
| 14 | 1198 |
| 15 | 1606 |
| 16 | 2454 |
| 17 | 3782 |
| 18 | 4997 |
| 19 | 7245 |
| 20 | 10543 |
| 21 | 13711 |
| 22 | 19092 |
| 23 | 26612 |
| 24 | 34076 |
| 25 | 45948 |
| 26 | 61930 |
| 27 | 78154 |
| 28 | 102654 |
| 29 | 134670 |
| 30 | 167688 |
| 31 | 215496 |
| 32 | 276480 |
| 33 | 340080 |
| 34 | 429030 |
| 35 | 540246 |
| 36 | 657162 |
| 37 | 815994 |
| 38 | 1011264 |
| 39 | 1217712 |
| 40 | 1491336 |
| 41 | 1822920 |
| 42 | 2174898 |
| 43 | 2631618 |
| 44 | 3178230 |
| 45 | 3760086 |
| 46 | 4501332 |
| 47 | 5378868 |
| 48 | 6314748 |
| 49 | 7487964 |
| 50 | 8863635 |
[1,1,1,2,6,21,112,853,111,181,323,437,717,1198, 1606,2454,3782,4997,7245,10543,13711,19092,26612, 34076,45948,61930,78154,102654,134670,167688, 215496,276480,340080,429030,540246,657162,815994, 1011264,1217712,1491336,1822920,2174898,2631618, 3178230,3760086,4501332,5378868,6314748,7487964, 8863635] |