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 A241125 Number of n X 2 0..2 arrays with no element equal to exactly two horizontal and vertical neighbors, with new values 0..2 introduced in row major order. 1
 2, 9, 54, 325, 1965, 11876, 71793, 434007, 2623694, 15861001, 95884409, 579649484, 3504151829, 21183629803, 128061281038, 774168159805, 4680074530261, 28292428888436, 171036065180937, 1033963386740399, 6250613190784174 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,1 LINKS R. H. Hardin, Table of n, a(n) for n = 1..210 FORMULA Empirical: a(n) = 6*a(n-1) + 2*a(n-2) - 9*a(n-3) - 10*a(n-4) + 8*a(n-5) for n>6. Empirical g.f.: x*(1 - x)*(1 - 2*x)*(2 + 3*x + x^2 - 2*x^3) / (1 - 6*x - 2*x^2 + 9*x^3 + 10*x^4 - 8*x^5). - Colin Barker, Oct 29 2018 EXAMPLE Some solutions for n=4: ..0..1....0..1....0..0....0..1....0..1....0..1....0..1....0..1....0..0....0..1 ..1..2....0..1....1..2....2..0....0..2....1..0....1..0....1..2....1..2....0..1 ..2..0....1..2....0..1....0..1....1..1....0..1....1..2....1..0....0..2....1..0 ..1..1....2..0....1..2....0..1....2..2....0..2....2..0....0..1....0..1....1..0 CROSSREFS Column 2 of A241130. Sequence in context: A360454 A073986 A223943 * A089436 A000168 A307442 Adjacent sequences: A241122 A241123 A241124 * A241126 A241127 A241128 KEYWORD nonn AUTHOR R. H. Hardin, Apr 16 2014 STATUS approved

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Last modified September 29 23:31 EDT 2023. Contains 365781 sequences. (Running on oeis4.)