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A326178型
{1..n}的子集数,其乘积等于其和。
6
0, 1, 2, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 38, 39, 40, 41, 42, 43, 44, 45, 46, 47, 48, 49, 50, 51, 52, 53, 54, 55, 56, 57, 58, 59, 60, 61, 62, 63, 64, 65, 66, 67
抵消
0,3
评论
等同于A001477号(非负整数),去掉3。
例子
a(1)=1到a(9)=10子集:
{1} {1} {1} {1} {1} {1} {1} {1} {1}
{2} {2} {2} {2} {2} {2} {2} {2}
{3} {3} {3} {3} {3} {3} {3}
{1,2,3} {4} {4} {4} {4} {4} {4}
{1,2,3} {5} {5} {5} {5} {5}
{1,2,3} {6} {6} {6} {6}
{1,2,3} {7} {7} {7}
{1,2,3} {8} {8}
{1,2,3} {9}
{1,2,3}
数学
表[Length[Select[Subsets[Range[n]],Times@@#==Plus@@#&]],{n,0,10}]
关键词
非n,哑的
作者
古斯·怀斯曼2019年6月13日
状态
经核准的