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A326117型 |
| 不包含两个或多个不同元素乘积的{1..n}的子集数。 |
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20
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1, 2, 3, 5, 9, 17, 29, 57, 101, 201, 365, 729, 1233, 2465, 4593, 8297, 15921, 31841, 55953, 111905, 195713, 362337, 697361, 1394721, 2334113, 4668225, 9095393, 17225313, 31242785, 62485569, 106668609, 213337217, 392606529, 755131841, 1491146913, 2727555425, 4947175713
(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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0,2
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评论
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链接
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配方奶粉
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示例
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a(6)=28组:
{}{1}{2,3}{2,3,4}{2,3,4,5}
{2} {2,4} {2,3,5} {2,4,5,6}
{3} {2,5} {2,4,5} {3,4,5,6}
{4} {2,6}{2,4,6}
{5} {3,4} {2,5,6}
{6} {3,5} {3,4,5}
{3,6}{3,4,6}
{4,5} {3,5,6}
{4,6} {4,5,6}
{5,6}
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数学
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表[Length[Select[Subsets[Range[n]],Intersection[#,Select[Times@@@Subsets[#,{2}],#<=n&]]=={}&]],{n,0,20}]
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交叉参考
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囊性纤维变性。A007865号,A051026号,A103580号,A196724号,A326020型,A326023型,A326076型,A326078型,A326079型,A326081型,A326116型,A308542型.
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关键词
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非n
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作者
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扩展
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状态
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经核准的
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