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A255785 Number of (n+2) X (1+2) 0..1 arrays with no 3 x 3 subblock diagonal sum 2 and no antidiagonal sum 2 and no row sum 0 and no column sum 0. 1
90, 177, 361, 715, 1478, 2969, 6186, 12534, 26219, 53487, 112079, 229756, 481725, 990964, 2077526, 4284777, 8978859, 18554317, 38857870, 80416809, 168307678, 348718298, 729394343, 1512628937, 3162067127, 6562395892, 13711273601 (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) + 5*a(n-2) - 2*a(n-3) - 6*a(n-4) - 7*a(n-5) + 6*a(n-6) + 3*a(n-7) - 6*a(n-8) + 5*a(n-9) + 5*a(n-10) + 5*a(n-11) + 2*a(n-12).

Empirical g.f.: x*(90 + 87*x - 266*x^2 - 351*x^3 - 148*x^4 + 330*x^5 + 122*x^6 - 56*x^7 + 409*x^8 + 369*x^9 + 282*x^10 + 88*x^11) / ((1 + x)*(1 - 2*x - 3*x^2 + 5*x^3 + x^4 + 6*x^5 - 12*x^6 + 9*x^7 - 3*x^8 - 2*x^9 - 3*x^10 - 2*x^11)). - Colin Barker, Dec 19 2018

EXAMPLE

Some solutions for n=4:

..1..1..1....1..1..1....1..0..0....1..1..0....1..1..1....0..1..1....1..0..1

..0..1..1....1..1..0....1..0..1....0..1..0....1..0..1....1..0..0....0..1..0

..1..0..1....1..0..1....0..1..0....0..0..1....0..1..0....0..1..0....1..0..1

..0..1..0....1..1..0....1..0..1....1..0..1....1..0..1....0..0..1....0..1..0

..1..0..1....1..0..1....1..1..0....0..1..1....1..0..1....1..0..1....1..0..1

..1..0..0....1..0..0....1..0..1....1..0..1....0..1..0....0..1..0....0..0..1

CROSSREFS

Column 1 of A255792.

Sequence in context: A119895 A270266 A255792 * A119896 A179697 A211442

Adjacent sequences:  A255782 A255783 A255784 * A255786 A255787 A255788

KEYWORD

nonn

AUTHOR

R. H. Hardin, Mar 06 2015

STATUS

approved

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Last modified July 24 20:26 EDT 2021. Contains 346273 sequences. (Running on oeis4.)