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A253021 Number of (n+2) X (4+2) 0..3 arrays with every consecutive three elements in every row and column not having exactly two distinct values, and in every diagonal and antidiagonal having exactly two distinct values, and new values 0 upwards introduced in row major order. 1
63, 91, 120, 155, 230, 296, 369, 546, 712, 893, 1322, 1722, 2155, 3190, 4158, 5203, 7702, 10040, 12561, 18594, 24240, 30325, 44890, 58522, 73211, 108374, 141286, 176747, 261638, 341096, 426705, 631650, 823480, 1030157, 1524938, 1988058 (list; graph; refs; listen; history; text; internal format)
OFFSET
1,1
LINKS
FORMULA
Empirical: a(n) = 3*a(n-3) - a(n-6) - a(n-9) for n>12.
Empirical g.f.: x*(63 + 91*x + 120*x^2 - 34*x^3 - 43*x^4 - 64*x^5 - 33*x^6 - 53*x^7 - 56*x^8 + 4*x^9 + 5*x^10 + 2*x^11) / ((1 - x)*(1 + x + x^2)*(1 - 2*x^3 - x^6)). - Colin Barker, Dec 08 2018
EXAMPLE
Some solutions for n=4:
..0..1..2..0..1..3....0..1..2..0..3..2....0..1..2..3..1..2....0..1..2..0..1..2
..0..0..0..0..0..0....0..0..0..0..0..0....2..2..2..2..2..2....2..1..0..2..1..0
..0..2..1..0..2..1....0..2..3..0..2..1....1..3..2..1..3..2....1..1..1..1..1..1
..0..1..2..0..1..2....0..3..2..0..1..2....3..1..2..3..1..2....0..1..2..0..1..2
..0..0..0..0..0..0....0..0..0..0..0..0....2..2..2..2..2..2....2..1..0..2..1..0
..0..3..1..0..2..1....0..2..1..0..2..1....1..3..2..1..0..2....1..1..1..1..1..1
CROSSREFS
Column 4 of A253025.
Sequence in context: A062375 A343025 A343003 * A039480 A023688 A118157
KEYWORD
nonn
AUTHOR
R. H. Hardin, Dec 26 2014
STATUS
approved

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Last modified July 19 13:41 EDT 2024. Contains 374394 sequences. (Running on oeis4.)