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A139753号 |
| a(2n)=a(2n-1)后的下一个立方体,a(2n+1)=a。 |
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1
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1, 8, 9, 27, 36, 64, 81, 125, 144, 216, 225, 343, 361, 512, 529, 729, 784, 1000, 1024, 1331, 1369, 1728, 1764, 2197, 2209, 2744, 2809, 3375, 3481, 4096, 4225, 4913, 5041, 5832, 5929, 6859, 6889, 8000, 8100, 9261, 9409, 10648, 10816, 12167, 12321, 13824
(列表;图表;参考文献;听;历史;文本;内部格式)
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抵消
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1,2
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评论
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具有偶数指数的项是n^3的立方体,其中n=2,3,。。。(所有整数>1),而奇数指数项为平方m^3,m=1,3,6,9,12,15,19,23,28,32,37,42,47,53,59,65,71,77,83,90,97104111118126133,141,149,157,165,173,182,190,199,208,217,226,235,244,253,263,273,282,292,302,312,323,333,344,354,365,375,386,397,408,420,431,442,454,465,477,489,501,513,525,537,549,561,574,586,599,611,624,637,650,663,676,689,703,716,730,743,757,770,784,798,812,826,840,854,869,883,897,912,926,941,956,971,986,1001; 囊性纤维变性。A077121号整数正方形数<=n^3。
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链接
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例子
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a(1)=1视为正方形,
a(2)=8=最小立方体>a(1);
a(3)=9=最小二乘>a(2),
a(4)=27=最小立方体>a(3),
a(5)=36=最小二乘>a(4),
a(6)=64=最小立方体>a(5),
a(7)=81=最小二乘>a(6),
a(8)=125=最小立方体>a(7)。
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数学
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nxt[{n_,a_}]:={n+1,If[OddQ[n],(Floor[Surd[a,3]]+1)^3,(Floor[Sqrt[a]]+1,^2]};嵌套列表[nxt,{1,1},50][[全部,2]](*哈维·P·戴尔2022年2月9日*)
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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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