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| n | a(n) |
|---|---|
| 1 | 0 |
| 2 | 0 |
| 3 | 0 |
| 4 | 0 |
| 5 | 1 |
| 6 | 1 |
| 7 | 2 |
| 8 | 4 |
| 9 | 6 |
| 10 | 10 |
| 11 | 13 |
| 12 | 20 |
| 13 | 27 |
| 14 | 39 |
| 15 | 50 |
| 16 | 70 |
| 17 | 87 |
| 18 | 120 |
| 19 | 147 |
| 20 | 198 |
| 21 | 240 |
| 22 | 315 |
| 23 | 381 |
| 24 | 491 |
| 25 | 594 |
| 26 | 752 |
| 27 | 900 |
| 28 | 1130 |
| 29 | 1348 |
| 30 | 1676 |
| 31 | 1992 |
| 32 | 2449 |
| 33 | 2902 |
| 34 | 3540 |
| 35 | 4184 |
| 36 | 5065 |
| 37 | 5969 |
| 38 | 7181 |
| 39 | 8438 |
| 40 | 10095 |
| 41 | 11829 |
| 42 | 14078 |
| 43 | 16460 |
| 44 | 19495 |
| 45 | 22740 |
| 46 | 26818 |
| 47 | 31205 |
| 48 | 36662 |
| 49 | 42571 |
| 50 | 49836 |
[0,0,0,0,1,1,2,4,6,10,13,20,27,39,50,70,87,120, 147,198,240,315,381,491,594,752,900,1130,1348, 1676,1992,2449,2902,3540,4184,5065,5969,7181,8438, 10095,11829,14078,16460,19495,22740,26818,31205, 36662,42571,49836] |