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 A051223 Number of ways of placing n nonattacking superqueens on an n X n board. 20
 1, 0, 0, 0, 0, 0, 0, 0, 0, 4, 44, 156, 1876, 5180, 32516, 202900, 1330622, 8924976, 64492432, 495864256, 3977841852, 34092182276, 306819842212, 2883202816808, 28144109776812, 286022102245804 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,10 COMMENTS A superqueen moves like a queen and a knight. A linear time algorithm giving an explicit solution for any n >= 10 for the n-super-queens-problem can be found at the link. Included is an online solver, implemented in Javascript. - Frank Schwellinger (nummer_eins(AT)web.de), Mar 19 2004 LINKS R. Oprisch, N x N SuperQueens Solutions Table D. Bill, Durango Bill's The N-Queens Problem V. Kotesovec, Non-attacking chess pieces, 6ed F. Schwellinger, Explicit Solution To the N-Super-Queens Problem. W. Schubert, N-Queens page CROSSREFS Cf. A051224, A000170. Sequence in context: A292454 A292734 A053314 * A265081 A077435 A271294 Adjacent sequences:  A051220 A051221 A051222 * A051224 A051225 A051226 KEYWORD nonn,nice,more AUTHOR Ulrich Schimke (ulrschimke(AT)aol.com) EXTENSIONS a(20) from Bill link added Jul 25 2006 a(21)-a(23) from R. Oprisch's website added by Max Alekseyev, Sep 29 2006 a(24)-a(26) from W. Schubert, Jul 31 2009, Nov 29 2009, Jan 18 2011 STATUS approved

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Last modified December 17 07:54 EST 2018. Contains 318192 sequences. (Running on oeis4.)