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A252964 Number of (3+2) X (n+2) 0..4 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
297, 185, 259, 369, 605, 985, 1429, 2421, 3907, 6027, 9989, 16623, 25801, 43767, 71599, 116257, 192617, 324273, 522253, 887501, 1465051, 2445931, 4064909, 6900751, 11349313, 19365335, 32221303, 54651057, 91301921, 156087937 (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) + 6*a(n-2) - a(n-3) - 15*a(n-4) - 20*a(n-5) + 27*a(n-6) + 53*a(n-7) - 14*a(n-8) - 51*a(n-9) - 45*a(n-10) + 60*a(n-11) + 18*a(n-12) - 18*a(n-13) for n>15.

Empirical g.f.: x*(297 - 112*x - 1708*x^2 - 703*x^3 + 3322*x^4 + 7140*x^5 - 3251*x^6 - 14334*x^7 - 2288*x^8 + 9945*x^9 + 14610*x^10 - 10506*x^11 - 5994*x^12 + 3384*x^13 + 216*x^14) / ((1 - x)*(1 + x - x^2)*(1 - x - x^2)*(1 - 3*x^2)*(1 - 2*x^3)*(1 - 3*x^3)). - Colin Barker, Dec 07 2018

EXAMPLE

Some solutions for n=2:

..0..1..0..0....0..1..1..2....0..1..1..2....0..1..1..2....0..0..1..1

..1..2..1..1....1..0..1..1....2..2..3..3....2..0..0..1....2..2..3..3

..3..3..2..2....3..3..1..3....3..0..0..1....3..4..4..0....4..4..0..0

..4..4..3..4....2..1..1..0....4..4..2..2....1..2..2..4....1..1..2..2

..1..1..4..1....1..2..1..1....1..3..3..0....0..3..3..2....3..3..4..4

CROSSREFS

Row 3 of A252961.

Sequence in context: A223847 A223873 A223798 * A224601 A134260 A260924

Adjacent sequences:  A252961 A252962 A252963 * A252965 A252966 A252967

KEYWORD

nonn

AUTHOR

R. H. Hardin, Dec 25 2014

STATUS

approved

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Last modified January 27 20:58 EST 2022. Contains 350633 sequences. (Running on oeis4.)