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 A192258 Number of n X n symmetric binary matrices with each element either the sum mod 2 of its horizontal neighbors or the sum mod 2 of its vertical neighbors 1
 1, 2, 3, 10, 52, 305, 3336, 53160, 1210187, 43234473, 2296063392, 180971357507, 21523051916415, 3822241812458992, 1013512678870403979, 402404564958432626790, 238779216876700299752228 (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 5X5 ..1..1..0..1..1....1..1..0..0..0....1..1..0..1..1....0..0..0..1..0 ..1..1..0..0..0....1..1..0..1..0....1..0..1..1..0....0..0..0..1..0 ..0..0..0..0..0....0..0..1..1..0....0..1..1..0..1....0..0..0..0..0 ..1..0..0..0..0....0..1..1..1..0....1..1..0..1..1....1..1..0..0..0 ..1..0..0..0..0....0..0..0..0..0....1..0..1..1..1....0..0..0..0..0 CROSSREFS Sequence in context: A020098 A013081 A054921 * A052561 A181927 A066526 Adjacent sequences:  A192255 A192256 A192257 * A192259 A192260 A192261 KEYWORD nonn AUTHOR R. H. Hardin Jun 26 2011 STATUS approved

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Last modified April 2 19:05 EDT 2020. Contains 333190 sequences. (Running on oeis4.)