In the paper, we prove that the edge number of the Subgraph with maximal edge number of cube graph is equal to the number of 1 in (0,1)-string all integers between 1 and its verter number.

本文中，我们证明了立方图的极大边数子图的边数等于从1到它的点数之间所有正整数的（0，1）——串表示中1的个数。

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It only remains to replace each edge of this diagram by a suitable subgraph which bears the information previously given by the direction and colour.

剩下要做的事只是用适当的子图代替这个图解的每条边，使得原来用方向和颜色给出的信息由这个子图来担当。

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