A Lower Bound for the n-queens Problem

  title={A Lower Bound for the n-queens Problem},
  author={Michael Simkin and Zur Luria},
The n-queens puzzle is to place n mutually non-attacking queens on an n × n chess board. We present a simple randomized algorithm to construct such configurations. We first use a random greedy algorithm to construct an approximate toroidal n-queens configuration. In this well-known variant the diagonals wrap around the board from left to right and from top to bottom. We show that with high probability this algorithm succeeds in placing (1 − o(1))n queens on the board. Furthermore, by making… 

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