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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 1 |
| 3 | 4 |
| 4 | 8 |
| 5 | 5 |
| 6 | 22 |
| 7 | 42 |
| 8 | 40 |
| 9 | 120 |
| 10 | 265 |
| 11 | 286 |
| 12 | 764 |
| 13 | 1729 |
| 14 | 2198 |
| 15 | 5168 |
| 16 | 12144 |
| 17 | 17034 |
| 18 | 37702 |
| 19 | 88958 |
| 20 | 136584 |
| 21 | 288270 |
| 22 | 682572 |
| 23 | 1118996 |
| 24 | 2306464 |
| 25 | 5428800 |
| 26 | 9409517 |
| 27 | 19103988 |
| 28 | 44701696 |
| 29 | 80904113 |
| 30 | 163344502 |
| 31 | 379249288 |
| 32 | 711598944 |
| 33 | 1434840718 |
| 34 | 3308997062 |
| 35 | 6391673638 |
| 36 | 12921383032 |
| 37 | 29611074174 |
| 38 | 58602591708 |
| 39 | 119001063028 |
| 40 | 271331133136 |
| 41 | 547872065136 |
| 42 | 1119204224666 |
| 43 | 2541384297716 |
| 44 | 5219606253184 |
| 45 | 10733985041978 |
| 46 | 24300914061436 |
| 47 | 50635071045768 |
| 48 | 104875736986272 |
| 49 | 236934212877684 |
| 50 | 499877970985660 |
[1,1,4,8,5,22,42,40,120,265,286,764,1729,2198, 5168,12144,17034,37702,88958,136584,288270,682572, 1118996,2306464,5428800,9409517,19103988,44701696, 80904113,163344502,379249288,711598944,1434840718, 3308997062,6391673638,12921383032,29611074174, 58602591708,119001063028,271331133136, 547872065136,1119204224666,2541384297716, 5219606253184,10733985041978,24300914061436, 50635071045768,104875736986272,236934212877684, 499877970985660] |