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A317142型 |
| n的严格整数分区的细化有序对的数目。 |
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4
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1, 1, 1, 3, 3, 5, 9, 12, 16, 24, 37, 47, 68, 90, 123, 180, 228, 307, 408, 540, 694, 970, 1207, 1598, 2048, 2669, 3357, 4382, 5599, 7109, 8990, 11428, 14330, 18144, 22652, 28343, 35746, 44269, 55094, 68384, 84780, 104477, 129360, 158682, 195323, 240177, 293704
(列表;图表;参考;听;历史;文本;内部格式)
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抵消
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0,4
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评论
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如果x和y是同一整数的严格分区,并且可以通过进一步划分y的部分、展平和排序来生成x,那么x<=y。
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链接
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例子
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a(9)=24个细化有序对:
(9) <=(9)
(5,4)<=(9) (5,4)<=(5,4)
(6,3)<=(9) (6,3)<=(6,3)
(7,2)<=(9) (7,2)<=(7,2)
(8,1)<=(9) (8,1)<=(8,1)
(4,3,2)<=(9) (4,3,2)<=(5,4) (4,3,2)<=(6,3) (4,3,2)<=(7,2) (4,3,2)<=(4,3,2)
(5,3,1)<=(9) (5,3,1)<=(5,4) (5,3,1)<=(6,3) (5,3,1)<=(8,1) (5,3,1)<=(5,3,1)
(6,2,1)<=(9) (6,2,1)<=(6,3) (6,2,1)<=(7,2) (6,2,1)<=(8,1) (6,2,1)<=(6,2,1)
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数学
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sps[{}]:={{}};sps[set:{i_,___}]:=联接@@函数[s,前缀[#,s]和/@sps[Complement[set,s]]/@Cases[子集[set],{i,___}];
mps[set_]:=联合[Sort[Sort/@(#/.x_Integer:>set[[x]])]&/@sps[Range[Length[set]]];
表[Sum[Length[Unination[Select[Sort/@Map[Total,mps[ptn],{2}],UnnameQ@#&]],{ptn,Select[IntegerPartitions[n],UnnameQ@#&]}],{n,30}]
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交叉参考
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关键词
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非n
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作者
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状态
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经核准的
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