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 A213599 Number of n X n binary matrices with zero diagonal and no 2-loops or directed 3-loops (3-loop: x(i,j)*x(j,k)*x(k,i)=1, and i,j,k all different) 0
 1, 3, 25, 549, 30535, 4168935, 1362083785, 1042729407045 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,2 LINKS EXAMPLE Some solutions for n=4 ..0..0..0..0....0..0..0..0....0..1..1..0....0..0..1..0....0..1..0..1 ..1..0..1..0....0..0..0..1....0..0..0..0....1..0..1..1....0..0..0..1 ..1..0..0..0....0..0..0..1....0..1..0..0....0..0..0..0....1..0..0..0 ..0..0..0..0....0..0..0..0....0..0..1..0....0..0..1..0....0..0..0..0 CROSSREFS Sequence in context: A306783 A003024 A224679 * A179473 A248417 A306795 Adjacent sequences:  A213596 A213597 A213598 * A213600 A213601 A213602 KEYWORD nonn AUTHOR R. H. Hardin Jun 14 2012 STATUS approved

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Last modified August 1 00:13 EDT 2021. Contains 346377 sequences. (Running on oeis4.)