Recently Mertens and Moore (2019 Phys . Rev . Lett . 123 230605) showed that site percolation ‘is odd’. By this they mean that on an M × N square lattice the number of distinct site configurations that allow for vertical percolation is odd. We report here an alternative proof, based on recursive use of geometric symmetry, for both free and periodic boundary conditions.

中文翻译：

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关于渗流的奇异性

最近Mertens和Moore（2019 Phys.Rev.Lett.123230605）表明，站点渗流``很奇怪''。他们的意思是，在M×N的方格上，允许垂直渗滤的不同位点构型的数量是奇数。我们在此报告基于自由和周期性边界条件的几何对称的递归使用的另一种证明。