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 A197102 Half the number of n X 1 0..3 arrays with no element equal to the average of its horizontal and vertical neighbors. 1
 2, 6, 16, 61, 212, 753, 2661, 9415, 33302, 117802, 416703, 1474018, 5214089, 18443961, 65242401, 230783990, 816359440, 2887733833, 10214871388, 36133384697, 127815754113, 452126672783, 1599321849338, 5657331300590 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,1 COMMENTS Column 1 of A197109. LINKS R. H. Hardin, Table of n, a(n) for n = 1..200 FORMULA Empirical: a(n) = 2*a(n-1) +5*a(n-2) +3*a(n-3) -4*a(n-4) -4*a(n-5) for n>6. Empirical g.f.: x*(2 + 2*x - 6*x^2 - 7*x^3 + 8*x^5) / (1 - 2*x - 5*x^2 - 3*x^3 + 4*x^4 + 4*x^5). - Colin Barker, May 11 2018 EXAMPLE Some solutions for 4 X 4: ..0....0....0....0....1....1....0....1....1....1....1....0....0....0....1....1 ..1....1....3....3....0....0....3....3....0....0....2....1....3....1....0....2 ..1....0....3....2....3....0....3....0....0....1....0....1....0....0....3....0 ..0....3....1....0....2....2....2....2....1....0....2....3....1....2....0....1 CROSSREFS Cf. A197109. Sequence in context: A027742 A324062 A033301 * A093113 A150030 A150031 Adjacent sequences:  A197099 A197100 A197101 * A197103 A197104 A197105 KEYWORD nonn AUTHOR R. H. Hardin, Oct 10 2011 STATUS approved

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Last modified November 30 21:20 EST 2021. Contains 349426 sequences. (Running on oeis4.)