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 A202043 Number of zero-sum nX4 -1..1 arrays with every element unequal to at most two horizontal and vertical neighbors 1
 19, 335, 2921, 31753, 359017, 4188917, 49553277, 594443301, 7206865523, 88120417529, 1084547246367, 13417760493253, 166705101517923, 2078489858665207, 25992085202674059, 325869090446388117 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,1 COMMENTS Column 4 of A202047 LINKS R. H. Hardin, Table of n, a(n) for n = 1..31 EXAMPLE Some solutions for n=4 ..1..1.-1.-1....1..1.-1..0...-1..1..1.-1....1.-1..1..1....0..1..1..0 .-1..1..1.-1....0.-1.-1..0....1..0..0.-1....1.-1..0..0....0..0..0..0 .-1..1..1.-1....0.-1..1..1....1..0..0.-1....1.-1..0..0....1.-1.-1.-1 .-1.-1..1..1...-1.-1..1..1....1..1.-1.-1...-1.-1..0..0....1.-1..0..0 CROSSREFS Sequence in context: A014900 A121324 A093973 * A142549 A049629 A162805 Adjacent sequences:  A202040 A202041 A202042 * A202044 A202045 A202046 KEYWORD nonn AUTHOR R. H. Hardin Dec 10 2011 STATUS approved

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Last modified December 12 00:07 EST 2018. Contains 318052 sequences. (Running on oeis4.)