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 A201956 Number of zero-sum nX3 -3..3 arrays with every element unequal to at most two horizontal and vertical neighbors 1
 37, 1587, 17091, 303955, 4735345, 85454789, 1489376611, 27222524599, 493561989579, 9124430335331, 168519041238653, 3142665027511853, 58661584782394781, 1101133968614654601, 20697996312691430763 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,1 COMMENTS Column 3 of A201958 LINKS R. H. Hardin, Table of n, a(n) for n = 1..20 EXAMPLE Some solutions for n=3 ..1.-2.-2....2..2..2....1..0..1...-1..1..1....2..3..3....2..2.-1....0.-2..3 ..1..1.-2....0..0..0...-2..0..1...-1..2..2...-3.-3..3....2..0..0....1.-2..3 .-1..1..3....0.-3.-3...-2..0..1...-3..2.-3...-1.-3.-1...-2..0.-3....1.-2.-2 CROSSREFS Sequence in context: A231543 A279330 A009695 * A322097 A260667 A130013 Adjacent sequences:  A201953 A201954 A201955 * A201957 A201958 A201959 KEYWORD nonn AUTHOR R. H. Hardin Dec 06 2011 STATUS approved

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Last modified December 2 06:44 EST 2020. Contains 338868 sequences. (Running on oeis4.)