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 A215786 Number of permutations of 0..floor((n*8-1)/2) on even squares of an nX8 array such that each row, column, diagonal and (downwards) antidiagonal of even squares is increasing 1
 1, 5, 110, 932, 26451, 234217, 6812794, 60485308, 1761748159, 15643423061, 455678075546, 4046220880948, 117863060852067, 1046572601513969, 30485799411892266, 270700616010831020, 7885286478349158743 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,2 COMMENTS Column 8 of A215788 LINKS R. H. Hardin, Table of n, a(n) for n = 1..210 FORMULA Empirical: a(n) = 272*a(n-2) -3439*a(n-4) -3336*a(n-6) +140*a(n-8) EXAMPLE Some solutions for n=4 ..0..x..1..x..3..x..7..x....0..x..1..x..2..x..3..x....0..x..1..x..2..x..5..x ..x..2..x..4..x..9..x.10....x..4..x..6..x..7..x..8....x..3..x..4..x..7..x.11 ..5..x..6..x.11..x.12..x....5..x..9..x.10..x.12..x....6..x..8..x..9..x.13..x ..x..8..x.13..x.14..x.15....x.11..x.13..x.14..x.15....x.10..x.12..x.14..x.15 CROSSREFS Sequence in context: A177680 A281762 A265082 * A053133 A203367 A322631 Adjacent sequences:  A215783 A215784 A215785 * A215787 A215788 A215789 KEYWORD nonn AUTHOR R. H. Hardin Aug 23 2012 STATUS approved

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Last modified August 10 13:30 EDT 2020. Contains 336381 sequences. (Running on oeis4.)