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A206265 Number of (n+1) X 7 0..1 arrays with the number of rightwards and downwards edge increases in each 2 X 2 subblock equal to the number in all its horizontal and vertical neighbors. 1
105, 128, 339, 800, 1725, 3440, 6444, 11448, 19457, 31832, 50397, 77528, 116289, 170552, 245166, 346112, 480709, 657808, 888039, 1184048, 1560789, 2035808, 2629584, 3365864, 4272057, 5379624, 6724529, 8347688, 10295481, 12620264 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

Column 6 of A206267.

LINKS

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

FORMULA

Empirical: a(n) = 7*a(n-1) - 20*a(n-2) + 28*a(n-3) - 14*a(n-4) - 14*a(n-5) + 28*a(n-6) - 20*a(n-7) + 7*a(n-8) - a(n-9) for n>10.

Empirical g.f.: x*(105 - 607*x + 1543*x^2 - 1953*x^3 + 791*x^4 + 1135*x^5 - 1938*x^6 + 1302*x^7 - 436*x^8 + 60*x^9) / ((1 - x)^8*(1 + x)). - Colin Barker, Jun 15 2018

EXAMPLE

Some solutions for n=4:

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

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

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

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

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

CROSSREFS

Cf. A206267.

Sequence in context: A033268 A325903 A095643 * A253022 A267891 A097217

Adjacent sequences:  A206262 A206263 A206264 * A206266 A206267 A206268

KEYWORD

nonn

AUTHOR

R. H. Hardin, Feb 05 2012

STATUS

approved

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Last modified September 19 10:41 EDT 2020. Contains 337178 sequences. (Running on oeis4.)