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| n | a(n) |
|---|---|
| 0 | 0 |
| 1 | 0 |
| 2 | 1 |
| 3 | 2 |
| 4 | 2 |
| 5 | 6 |
| 6 | 3 |
| 7 | 12 |
| 8 | 4 |
| 9 | 20 |
| 10 | 5 |
| 11 | 30 |
| 12 | 6 |
| 13 | 42 |
| 14 | 7 |
| 15 | 56 |
| 16 | 8 |
| 17 | 72 |
| 18 | 9 |
| 19 | 90 |
| 20 | 10 |
| 21 | 110 |
| 22 | 11 |
| 23 | 132 |
| 24 | 12 |
| 25 | 156 |
| 26 | 13 |
| 27 | 182 |
| 28 | 14 |
| 29 | 210 |
| 30 | 15 |
| 31 | 240 |
| 32 | 16 |
| 33 | 272 |
| 34 | 17 |
| 35 | 306 |
| 36 | 18 |
| 37 | 342 |
| 38 | 19 |
| 39 | 380 |
| 40 | 20 |
| 41 | 420 |
| 42 | 21 |
| 43 | 462 |
| 44 | 22 |
| 45 | 506 |
| 46 | 23 |
| 47 | 552 |
| 48 | 24 |
| 49 | 600 |
| 50 | 25 |
| 51 | 650 |
| 52 | 26 |
| 53 | 702 |
| 54 | 27 |
| 55 | 756 |
| 56 | 28 |
| 57 | 812 |
| 58 | 29 |
| 59 | 870 |
| 60 | 30 |
| 61 | 930 |
| 62 | 31 |
| 63 | 992 |
| 64 | 32 |
| 65 | 1056 |
| 66 | 33 |
[0,0,1,2,2,6,3,12,4,20,5,30,6,42,7,56,8,72,9,90, 10,110,11,132,12,156,13,182,14,210,15,240,16,272, 17,306,18,342,19,380,20,420,21,462,22,506,23,552, 24,600,25,650,26,702,27,756,28,812,29,870,30,930, 31,992,32,1056,33] |