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 A252725 Number of (6+2) X (n+2) 0..3 arrays with every consecutive three elements in every row and diagonal having exactly two distinct values, and in every column and antidiagonal not having exactly two distinct values, and new values 0 upwards introduced in row major order. 1
 165, 154, 170, 178, 214, 262, 270, 354, 434, 466, 622, 790, 846, 1170, 1490, 1618, 2254, 2902, 3150, 4434, 5714, 6226, 8782, 11350, 12366, 17490, 22610, 24658, 34894, 45142, 49230, 69714, 90194, 98386, 139342, 180310, 196686, 278610, 360530, 393298 (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) = -a(n-1) +3*a(n-3) +3*a(n-4) -2*a(n-6) -2*a(n-7) for n>9. Empirical g.f.: x*(165 + 319*x + 324*x^2 - 147*x^3 - 565*x^4 - 496*x^5 - 182*x^6 + 86*x^7 + 8*x^8) / ((1 - x)*(1 + x)*(1 + x + x^2)*(1 - 2*x^3)). - Colin Barker, Dec 06 2018 EXAMPLE Some solutions for n=4: ..0..1..1..0..1..1....0..1..0..0..1..0....0..1..0..0..1..0....0..1..0..0..2..0 ..2..1..2..2..1..2....0..0..1..0..0..1....1..1..2..1..1..2....0..0..1..0..0..2 ..1..1..0..1..1..0....0..2..2..0..2..2....2..1..1..2..1..1....0..3..3..0..3..3 ..0..1..1..0..1..1....0..3..0..0..1..0....0..1..0..0..1..0....0..2..0..0..1..0 ..2..1..2..2..1..2....0..0..3..0..0..1....1..1..2..1..1..2....0..0..2..0..0..1 ..1..1..0..1..1..0....0..2..2..0..2..2....3..1..1..2..1..1....0..3..3..0..3..3 ..3..1..1..0..1..1....0..3..0..0..3..0....0..1..0..0..1..0....0..1..0..0..2..0 ..2..1..2..2..1..2....0..0..3..0..0..3....1..1..3..1..1..2....0..0..1..0..0..2 CROSSREFS Row 6 of A252719. Sequence in context: A300057 A197440 A261758 * A168355 A083255 A259283 Adjacent sequences: A252722 A252723 A252724 * A252726 A252727 A252728 KEYWORD nonn AUTHOR R. H. Hardin, Dec 20 2014 STATUS approved

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Last modified December 8 11:46 EST 2023. Contains 367678 sequences. (Running on oeis4.)