An edge connects vertices x and y in the graph (where x < y) whenever the xth bit of the binary representation of y is nonzero. Thus, for instance, the neighbors of vertex 0 consist of all odd-numbered vertices, because the numbers whose 0th bit is nonzero are exactly the odd numbers. Vertex 1 has one smaller neighbor, vertex 0, as 1 is odd and vertex 0 is connected to all odd vertices. The larger neighbors of vertex 1 are all vertices with numbers congruent to 2 or 3 modulo 4, because those are exactly the numbers with a nonzero bit at index 1.; .
