  In site percolation, vertices (sites) of a graph are open with probability p,
and there is critical p, for which open vertices form an open path the long way
across a graph, so a vertex at the origin is a part of an infinite connected
open vertex set. Smirnov found that for triangular lattice critical p is 0.5,
but there is the traversal, from the origin upwards, so that an infinite
connected open vertex set exists for critical p=0.3535.
