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%I #28 Mar 29 2022 05:46:17
%S 0,0,0,0,0,0,0,0,0,0,0,2,2,0,0,12,17,0,0,60,82
%N Number of doubly symmetric characteristic solutions to the n-superqueens problem.
%C Superqueens are also called amazons. They combine the moves of queen and knight.
%D Martin Gardner, Fractal Music, Hypercards, and More, W H Freeman, 1991, page 238 (based on his column in Scientific American, June 1979).
%D D. E. Knuth, The Art of Computer Programming, Section 7.2.2.3 (draft, March 2022).
%e For n=12 the a(12)=2 solutions are
%e +-------------------------+ +-------------------------+
%e | . . . . A . . . . . . . | | . . . . A . . . . . . . |
%e | . . . . . . . . . A . . | | . . . . . . . . . A . . |
%e | . A . . . . . . . . . . | | . A . . . . . . . . . . |
%e | . . . . . A . . . . . . | | . . . . . . A . . . . . |
%e | . . . . . . . . . . . A | | . . . . . . . . . . . A |
%e | . . . . . . . . A . . . | | . . . A . . . . . . . . |
%e | . . . A . . . . . . . . | | . . . . . . . . A . . . |
%e | A . . . . . . . . . . . | | A . . . . . . . . . . . |
%e | . . . . . . A . . . . . | | . . . . . A . . . . . . |
%e | . . . . . . . . . . A . | | . . . . . . . . . . A . |
%e | . . A . . . . . . . . . | | . . A . . . . . . . . . |
%e | . . . . . . . A . . . . | | . . . . . . . A . . . . |
%e +-------------------------+ +-------------------------+
%Y A051224 = A352661 + A352662 + A352663.
%Y A051223 = 2*A352661 + 4*A352662 + 8*A352663 (when n>1).
%K nonn,more
%O 1,12
%A _Don Knuth_, Mar 25 2022
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