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%I #7 Mar 30 2012 18:59:35
%S 1,0,0,1,2,3,3,19,31,328,650,14542,37449,771570
%N Number of permutations with at most 2 queens on any torus diagonal, solutions similar on the torus count only once.
%C As A062167, also this sequence counts classes of "near n-queens solutions". In this sequence, two permutations p and q are considered similar iff there is a factor f, 0 < f < n, satisfying GCD (f,n) = 1, such that for all k from {0, ..., n-1} q (k * f mod n) = p (k) * f mod n or if q is a rotation, a reflection or a shift of such a q. In other words, also expansions are allowed which move the queen at (k, p(k)) to (f * k mod n, f * p(k) mod n). The sequence contains the objects of A062165.
%H M. Engelhardt, <a href="http://www.nqueens.de">The N queens problem</a>
%K nonn,more
%O 1,5
%A _Matthias Engelhardt_
%E Updated link that is transferred from people.freenet.de/nQueens to www.nqueens.de _Matthias Engelhardt_, Apr 21 2010