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 A201847 T(n,k)=Number of zero-sum nXk -1..1 arrays with every element equal to at least one horizontal or vertical neighbor 9
 0, 1, 1, 1, 5, 1, 3, 25, 25, 3, 1, 97, 125, 97, 1, 9, 411, 2019, 2019, 411, 9, 7, 1897, 17031, 54773, 17031, 1897, 7, 25, 8741, 259811, 1566319, 1566319, 259811, 8741, 25, 25, 41689, 2809217, 47249907, 109797321, 47249907, 2809217, 41689, 25, 83, 201985 (list; table; graph; refs; listen; history; text; internal format)
 OFFSET 1,5 COMMENTS Table starts ..0......1..........1.............3..............1...............9 ..1......5.........25............97............411............1897 ..1.....25........125..........2019..........17031..........259811 ..3.....97.......2019.........54773........1566319........47249907 ..1....411......17031.......1566319......109797321......8964073263 ..9...1897.....259811......47249907.....8964073263...1759241274383 ..7...8741....2809217....1459651671...697824874477.350714115254871 .25..41689...38543397...45844870481.56238345975057 .25.201985..461143387.1455414376611 .83.987407.6074619247 LINKS R. H. Hardin, Table of n, a(n) for n = 1..83 EXAMPLE Some solutions for n=4 k=4 .-1..0..0..0...-1..1..0..0...-1.-1..1..1....0.-1..1..1...-1..0..1.-1 .-1.-1.-1..0...-1..1.-1.-1...-1..1..0..0....0.-1..0..0...-1..0..1.-1 ..1..1..1..1....0..0..1..0....1..1..0..0....0..0..1.-1....0..0.-1.-1 ..0..0..0..0....0..0..1..0....1.-1.-1.-1....0..0..1.-1....1..1..1..1 CROSSREFS Sequence in context: A134894 A143700 A036790 * A185559 A275842 A147640 Adjacent sequences:  A201844 A201845 A201846 * A201848 A201849 A201850 KEYWORD nonn,tabl AUTHOR R. H. Hardin Dec 06 2011 STATUS approved

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Last modified December 8 14:38 EST 2019. Contains 329865 sequences. (Running on oeis4.)