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 A201841 Number of zero-sum nX2 -1..1 arrays with every element equal to at least one horizontal or vertical neighbor 1
 1, 5, 25, 97, 411, 1897, 8741, 41689, 201985, 987407, 4891069, 24457873, 123131033, 623695509, 3174983801, 16227954653, 83226630287, 428047598133, 2206766393985, 11399915802567, 58993096946055, 305739808201773, 1586610751415691 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,2 COMMENTS Column 2 of A201847 LINKS R. H. Hardin, Table of n, a(n) for n = 1..95 EXAMPLE Some solutions for n=8 .-1.-1...-1..0....1.-1....1..1....1..1...-1..0...-1.-1...-1.-1...-1.-1...-1..0 ..1..1...-1..0....1.-1....1.-1....1..0...-1..0....0.-1....1..1...-1.-1...-1..0 ..0..1....1..1....1..0....1.-1...-1..0....0..1....0..1....0..1....0..1....0..0 ..0..1...-1.-1...-1..0...-1.-1...-1..1....0..1....0..1....0..1....0..1....0..0 .-1..1....1.-1...-1..0....1..1...-1..1....0..0....1..1....0..0....0..0...-1..1 .-1..1....1..1....1..0....0..0....0..0...-1.-1...-1..1....0.-1...-1..1...-1..1 ..0.-1....1.-1....1.-1...-1.-1....0..0....0..1...-1..0....0.-1...-1..1....0..0 ..0.-1....1.-1....1.-1....0..0...-1.-1....0..1....0..0....0..0....1..1....1..1 CROSSREFS Sequence in context: A055343 A223945 A197085 * A146830 A022729 A098111 Adjacent sequences:  A201838 A201839 A201840 * A201842 A201843 A201844 KEYWORD nonn AUTHOR R. H. Hardin Dec 06 2011 STATUS approved

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