

A253019


Number of (n+2) X (2+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



37, 50, 83, 91, 133, 223, 243, 357, 595, 653, 959, 1589, 1761, 2583, 4253, 4765, 6979, 11413, 12939, 18921, 30715, 35267, 51485, 82919, 96507, 140637, 224603, 265189, 385735, 610573, 731865, 1062495, 1666165, 2028821, 2939531, 4565069, 5649843
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OFFSET

1,1


LINKS

R. H. Hardin, Table of n, a(n) for n = 1..210


FORMULA

Empirical: a(n) = 6*a(n3) 10*a(n6) +3*a(n9) for n>11.
Empirical g.f.: x*(37 + 50*x + 83*x^2  131*x^3  167*x^4  275*x^5 + 67*x^6 + 59*x^7 + 87*x^8  6*x^9  3*x^10) / ((1  3*x^3)*(1  3*x^3 + x^6)).  Colin Barker, Dec 08 2018


EXAMPLE

Some solutions for n=4:
..0..1..2..0....0..0..0..0....0..0..0..0....0..0..0..0....0..1..2..0
..2..2..2..2....1..2..0..1....1..2..0..3....1..0..2..1....3..0..2..3
..3..0..2..1....2..1..0..2....2..1..0..2....2..0..1..2....2..2..2..2
..0..3..2..0....0..0..0..0....0..0..0..0....0..0..0..0....0..3..2..0
..2..2..2..2....1..2..0..1....1..2..0..1....1..0..2..1....3..0..2..1
..1..0..2..3....2..3..0..2....2..3..0..2....2..0..1..2....2..2..2..2


CROSSREFS

Column 2 of A253025.
Sequence in context: A162556 A129072 A297911 * A298504 A074401 A323476
Adjacent sequences: A253016 A253017 A253018 * A253020 A253021 A253022


KEYWORD

nonn


AUTHOR

R. H. Hardin, Dec 26 2014


STATUS

approved



