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 A213608 Number of n X n binary matrices with zero diagonal and x(i,j)+x(j,k)+x(k,i) not equal to one for i,j,k all different 0
 1, 4, 25, 175, 1572, 19285, 321925, 7695406, 271013005 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,2 LINKS EXAMPLE Some solutions for n=4 ..0..1..1..1....0..0..0..1....0..1..1..1....0..1..1..0....0..1..1..1 ..1..0..0..1....0..0..1..1....1..0..1..1....1..0..1..1....1..0..1..0 ..1..0..0..1....1..0..0..1....1..1..0..0....0..1..0..1....1..0..0..0 ..0..1..1..0....1..1..1..0....1..1..1..0....1..1..0..0....1..1..0..0 CROSSREFS Sequence in context: A084210 A093683 A006348 * A324169 A213231 A051820 Adjacent sequences:  A213605 A213606 A213607 * A213609 A213610 A213611 KEYWORD nonn AUTHOR R. H. Hardin Jun 16 2012 STATUS approved

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Last modified January 23 03:15 EST 2022. Contains 350504 sequences. (Running on oeis4.)