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 A189873 Number of ways to place n nonattacking composite pieces queen + rider[1,3] on an n X n chessboard. 3
 1, 0, 0, 0, 0, 0, 0, 0, 0, 4, 56, 18, 116, 112, 408, 916, 2400, 7228, 27368, 111478, 445644, 1674860, 7624368, 38737270, 178933064 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,10 COMMENTS In fairy chess, the rider [1,3] is called a Camelrider. a(n) is also number of permutations p of 1,2,...,n satisfying |p(i+k)-p(i)|<>3k AND |p(j+3k)-p(j)|<>k AND |p(m+k)-p(m)|<>k for all i>=1, j>=1, m>=1, k>=1, i+k<=n, j+3k<=n, m+k<=n LINKS Table of n, a(n) for n=1..25. V. Kotesovec, Number of ways of placing non-attacking queens, kings, bishops and knights (in English and Czech) Wikipedia, Fairy chess piece CROSSREFS Cf. A102388, A189850 Sequence in context: A246968 A355073 A054751 * A358542 A359656 A329459 Adjacent sequences: A189870 A189871 A189872 * A189874 A189875 A189876 KEYWORD nonn,hard AUTHOR Vaclav Kotesovec, Apr 29 2011 STATUS approved

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Last modified October 1 13:59 EDT 2023. Contains 365826 sequences. (Running on oeis4.)