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 A208170 Number of n X 3 0..3 arrays with new values 0..3 introduced in row major order and no element equal to more than one of its immediate leftward or upward neighbors. 1
 5, 159, 8469, 473928, 26625693, 1496307201, 84091222866, 4725865313907, 265590215430897, 14925978329967384, 838829205068709369, 47141595663874099773, 2649323638611897879018, 148890075596000256587991 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,1 COMMENTS Column 3 of A208175. LINKS R. H. Hardin, Table of n, a(n) for n = 1..210 FORMULA Empirical: a(n) = 62*a(n-1) - 333*a(n-2) + 396*a(n-3) - 135*a(n-4) for n>5. Empirical g.f.: x*(5 - 151*x + 276*x^2 - 183*x^3 + 45*x^4) / ((1 - 5*x + 3*x^2)*(1 - 57*x + 45*x^2)). - Colin Barker, Jun 29 2018 EXAMPLE Some solutions for n=4: ..0..0..1....0..1..2....0..1..1....0..0..1....0..1..0....0..0..0....0..0..0 ..0..1..0....3..0..1....0..0..0....0..2..0....0..2..2....0..1..0....1..1..0 ..0..0..1....2..0..0....0..1..1....1..2..1....1..2..1....2..1..1....0..1..0 ..1..1..0....1..3..0....0..2..1....3..0..0....1..3..2....0..2..1....0..1..0 CROSSREFS Cf. A208175. Sequence in context: A155208 A321529 A156486 * A088694 A208583 A197310 Adjacent sequences:  A208167 A208168 A208169 * A208171 A208172 A208173 KEYWORD nonn AUTHOR R. H. Hardin, Feb 24 2012 STATUS approved

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Last modified December 8 04:31 EST 2019. Contains 329850 sequences. (Running on oeis4.)