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 A210926 Number of n X n 0..3 symmetric matrices with every element equal to one, two or three horizontal and vertical neighbors, and new values 0..3 introduced in lower triangle row major order 1
 0, 1, 4, 95, 9220, 3055073, 3000338892, 8812917082915, 76878364475257062, 1995945343880703817038, 154116672749530867319434810 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,3 LINKS EXAMPLE Some solutions for n=4 ..0..0..1..0....0..0..1..1....0..0..0..1....0..0..0..0....0..0..1..1 ..0..0..1..0....0..0..1..1....0..1..1..1....0..1..1..0....0..0..1..0 ..1..1..2..2....1..1..1..0....0..1..1..0....0..1..1..0....1..1..1..0 ..0..0..2..2....1..1..0..0....1..1..0..0....0..0..0..0....1..0..0..0 CROSSREFS Sequence in context: A220429 A210857 A220682 * A302121 A188895 A068114 Adjacent sequences: A210923 A210924 A210925 * A210927 A210928 A210929 KEYWORD nonn AUTHOR R. H. Hardin Mar 29 2012 STATUS approved

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Last modified March 30 19:10 EDT 2023. Contains 361622 sequences. (Running on oeis4.)