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A325787型 n的完美严格项链成分的数量。 5
1, 0, 1, 0, 0, 0, 2, 0, 0, 0, 0, 0, 4, 0, 0, 0, 0, 0, 0, 0, 2, 0, 0, 0, 0, 0, 0, 0, 0, 0, 10, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 12, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 8, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 12, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0 (列表;图表;参考;;历史;文本;内部格式)
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n的严格项链组合是不同正整数的有限序列与n之和,在其所有循环旋转中,n的字典序最小。换句话说,它是从最小部分开始的n的严格组合。循环子序列是连续项的序列,其中最后部分和第一部分也被认为是连续的。如果从1到n的每个正整数恰好是一个不同循环子序列的和,则n的项链合成是完美的。例如,组合(1,2,6,4)是完美的,因为它具有以下循环子序列和和:
1: (1)
2: (2)
3: (1,2)
4: (4)
5:(4,1)
6: (6)
7: (4,1,2)
8: (2,6)
9: (1,2,6)
10: (6,4)
11: (6,4,1)
12: (2,6,4)
13: (1,2,6,4)
a(n)>0的iffn=A002061号(k)=A004136号(k) 对于一些k-伯特·多贝莱尔2020年11月11日
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例子
a(1)=1到a(31)=10个完美严格的项链组成(空列未显示):
(1) (1,2)(1,2,4)(1,2,6,4)(1,3,10,2,5)(1,10,8,7,2,3)
(1,4,2) (1,3,2,7) (1,5,2,10,3) (1,13,6,4,5,2)
(1,4,6,2) (1,14,4,2,3,7)
(1,7,2,3) (1,14,5,2,6,3)
(1,2,5,4,6,13)
(1,2,7,4,12,5)
(1,3,2,7,8,10)
(1,3,6,2,5,14)
(1,5,12,4,7,2)
(1,7,3,2,4,14)
发件人伯特·多贝莱尔2020年11月11日:(开始)
匹配从a(57)到a(273)的非零项的合成,直至对称。
a(57)=12:
(1,2,10,19,4,7,9,5)
(1,3,5,11,2,12,17,6)
(1,3,8,2,16,7,15,5)
(1,4,2,10,18,3,11,8)
(1,4,22,7,3,6,2,12)
(1,6,12,4,21,3,2,8)
a(73)=8:
(1,2,4,8,16,5,18,9,10)
(1,4,7,6,3,28,2,8,14)
(1,6,4,24,13,3,2,12,8)
(1,11,8,6,4,3,2,22,16)
a(91)=12:
(1,2,6,18,22,7,5,16,4,10)
(1,3,9,11,6,8,2,5,28,18)
(1,4,2,20,8,9,23,10,3,11)
(1,4,3,10,2,9,14,6,26)
(1,5,4,13,3,8,7,12,2,36)
(1,6,9,11,29,4,8,2,3,18)
a(133)=36:
(1,2,9,8,14,4,43,7,6,10,5,24)
(1,2,12,31,25,4,9,10,7,11,16,5)
(1,2,14,4,37,7,8,27,5,6,13,9)
(1,2,14,12,32,19,6,5,4,18,13,7)
(1,3,8,9,5,19,23,16,13,2,28,6)
(1,3,12,34,21,2,8,9,5,6,7,25)
(1,3,23,24,6,22,10,18,2,5,8)
(1,4,7,3,16,2,6,17,20,9,13,35)
(1,4,16,3,15,10,12,14,17,33,2,6)
(1,4,19,20,27,3,6,25,7,8,2,11)
(1,4,20,3,40,10,9,2,15,16,6,7)
(1,5,12,21,29,11,3,16,4,22,2,7)
(1,7,13,12,3,11,5,18,4,2,48,9)
(1,8,10,5,7,21,4,2,11,3,26,35)
(1,14,3,2,4,7,21,8,25,10,12,26)
(1,14,10,20,7,6,3,2,17,4,8,41)
(1,15,5,3,25,2,7,4,6,12,14,39)
(1,22,14,20,5,13,8,3,4,2,10,31)
a(183)=40:
(1,2,13,7,5,14,34,6,4,33,18,17,21,8)
(1,2,21,17,11,5,9,4,26,6,47,15,12,7)
(1,2,28,14,5,6,9,12,48,18,4,13,16,7)
(1,3,5,6,25,32,23,10,18,2,17,7,22,12)
(1,3,12,7,20,14,44,6,5,24,2,28,8,9)
(1,3,24,6,12,14,11,55,7,2,8,5,16,19)
(1,4,6,31,3,13,2,7,14,12,17,46,8,19)
(1,4,8,52,3,25,18,2,9,24,6,10,7,14)
(1,4,20,2,12,3,6,7,33,11,8,10,35,31)
(1,5,2,24,15,29,14,21,13,4,33,3,9,10)
(1,5,23,27,42,3,4,11,2,19,12,10,16,8)
(1,6,8,22,4,5,33,21,3,20,32,16,2,10)
(1,8,3,10,23,5,56,4,2,14,15,17,7,18)
(1,8,21,45,6,7,11,17,3,2,10,4,23,25)
(1,9,5,40,3,4,21,35,16,18,2,6,11,12)
(1,9,14,26,4,2,11,5,3,12,27,34,7,28)
(1,9,21,25,3,4,8,5,6,16,2,36,14,33)
(1,10,22,34,27,12,3,4,2,14,24,5,8,17)
(1,10,48,9,19,4,8,6,7,17,3,2,34,15)
(1,12,48,6,2,38,3,22,7,10,11,5,4,14)
a(273)=12:
(1,2,4,8,16,32,27,26,11,9,45,13,10,29,5,17,18)
(1,3,12,10,31,7,27,2,6,5,19,20,62,14,9,28,17)
(1,7,3,15,33,5,24,68,14,6,7,4,9,19,12,34)
(1,7,12,44,25,41,9,17,6,22,33,13,2,3,11,23)
(1,7,31,2,11,3,9,36,17,4,22,6,18,72,5,10,19)
(1,21,11,50,39,13,6,4,14,16,25,26,3,2,7,8,27)
(结束)
数学
neckQ[q_]:=数组[OrderedQ[{q,RotateRight[q,#]}]&,长度[q]-1,1,And];
subalt[q_]:=并集[ReplaceList[q,{___,s_,___}:>{s}],删除事例[Replace List[g,{t___,__,u___}:>{u,t}],{}]];
表[Length[Select[Join@@Permutations/@Select[Integer Partitions[n],UnsameQ@@#&],neckQ[#]&&Sort[Total/@subalt[#]]==Range[n]&]],{n,30}]
交叉参考
关键词
非n
作者
古斯·怀斯曼2019年5月22日
扩展
来自的更多条款伯特·多贝莱尔2020年11月11日
状态
已批准

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上次修改时间:2024年4月16日10:08 EDT。包含371698个序列。(在oeis4上运行。)