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| n | a(n) |
|---|---|
| 1 | 0 |
| 2 | 1 |
| 3 | 1 |
| 4 | 3 |
| 5 | 6 |
| 6 | 3 |
| 7 | 7 |
| 8 | 22 |
| 9 | 22 |
| 10 | 7 |
| 11 | 15 |
| 12 | 84 |
| 13 | 150 |
| 14 | 84 |
| 15 | 15 |
| 16 | 31 |
| 17 | 346 |
| 18 | 1276 |
| 19 | 1276 |
| 20 | 346 |
| 21 | 31 |
| 22 | 63 |
| 23 | 1476 |
| 24 | 11538 |
| 25 | 23214 |
| 26 | 11538 |
| 27 | 1476 |
| 28 | 63 |
| 29 | 127 |
| 30 | 6322 |
| 31 | 102772 |
| 32 | 418912 |
| 33 | 418912 |
| 34 | 102772 |
| 35 | 6322 |
| 36 | 127 |
| 37 | 255 |
| 38 | 26844 |
| 39 | 890130 |
| 40 | 7290534 |
| 41 | 14673870 |
| 42 | 7290534 |
| 43 | 890130 |
| 44 | 26844 |
| 45 | 255 |
| 46 | 511 |
| 47 | 112666 |
| 48 | 7525876 |
| 49 | 123174016 |
| 50 | 496484776 |
| 51 | 496484776 |
| 52 | 123174016 |
| 53 | 7525876 |
| 54 | 112666 |
| 55 | 511 |
[0,1,1,3,6,3,7,22,22,7,15,84,150,84,15,31,346, 1276,1276,346,31,63,1476,11538,23214,11538,1476, 63,127,6322,102772,418912,418912,102772,6322,127, 255,26844,890130,7290534,14673870,7290534,890130, 26844,255,511,112666,7525876,123174016,496484776, 496484776,123174016,7525876,112666,511] |