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A243820型 |
| 半长度为n的Dyck路径的数量,使得长度为4的所有十六个连续阶梯图案至少出现一次。 |
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8
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38, 587, 4785, 31398, 190050, 1043248, 5324534, 25711105, 119092876, 533680433, 2329450085, 9955122396, 41824314441, 173289259905, 709861015186, 2880803895035, 11601285215222, 46422795985447, 184784743066842, 732324944072523, 2891815190097065, 11385122145001833
(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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10,1
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链接
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例子
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a(10)=38:101100111101000010,10101101001111000010,1010111100001010010010010,10101111001000010, 10111101001100001010, 10111101010000110010, 10111101010011000010, 11001011110000110100, 11001011110100001100, 11001101011110000100, 11001101111000010100, 11001111000010110100, 11001111010000101100, 11001111010110000100, 11001111011000010100, 11010010111100001100, 11010011110000101100, 11010110011110000100, 11010111100001001100, 11010111100001100100, 11010111100100001100, 11010111100110000100, 11011001111000010100, 11011110000101001100, 11011110000110010100, 11011110010100001100, 11011110011000010100. 这里1=向上=(1,1),0=向下=(1,-1)。
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MAPLE公司
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b: =proc(x,y,t,s)选项记忆`如果`(y<0或y>x,0,
`如果`(x=0,`if`(s={},1,0),`if'(nops)>x,0,添加(
b(x-1,y-1+2*j,irem(2*t+j,8),s减去{2*t+j}),j=0..1))
结束时间:
a: =n->加(b(2*n-3,l[],{$0..15}),l=[1,5],[1,6],[3,7]]):
seq(a(n),n=10..20);
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数学
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b[x_,y_,t_,s_List]:=b[x,y,t,s]=如果[y<0|y>x,0,如果[x==0,如果[s=={},1,0],如果[Length[s]>x,O,Sum[b[x-1,y-1+2j,Mod[2t+j,8],s~补码~{2t+j}],{j,0,1}]];
a[n]:=和[b[2n-3,序列@@l,范围[0,15]],{l,{1,5},{1,6},}3,7}}}];
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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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