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 A190655 Half the number of n X n symmetric binary matrices with no element unequal to a strict majority of its diagonal and antidiagonal neighbors 1
 1, 2, 4, 24, 224, 2862, 53010, 1527552, 65195940, 4097065492, 385902826186, 54089022594864, 11269850153217786, 3491854976674289164, 1609153719436211880868, 1102542409006001885651456 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,2 LINKS R. H. Hardin, Table of n, a(n) for n = 1..18 EXAMPLE Some solutions for n=5 with a(1,1)=0 ..0..1..1..0..1....0..1..0..0..1....0..1..0..1..1....0..1..0..0..1 ..1..0..0..1..1....1..0..1..1..0....1..0..1..1..0....1..0..1..1..0 ..1..0..0..1..0....0..1..1..0..0....0..1..1..0..0....0..1..0..0..1 ..0..1..1..0..0....0..1..0..0..1....1..1..0..0..1....0..1..0..0..0 ..1..1..0..0..0....1..0..0..1..0....1..0..0..1..0....1..0..1..0..0 CROSSREFS Sequence in context: A121892 A032107 A141307 * A038049 A151817 A265937 Adjacent sequences:  A190652 A190653 A190654 * A190656 A190657 A190658 KEYWORD nonn AUTHOR R. H. Hardin May 16 2011 STATUS approved

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Last modified December 2 18:11 EST 2021. Contains 349445 sequences. (Running on oeis4.)