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A186843 Number of (n+1) X 3 binary arrays with no 2 X 2 subblock diagonal sum less antidiagonal sum equal to any horizontal or vertical neighbor 2 X 2 subblock diagonal sum less antidiagonal sum. 1
50, 218, 970, 4194, 18246, 79778, 347530, 1514138, 6603034, 28783358, 125459410, 546925146, 2384168474, 10392867762, 45304600806, 197491613026, 860900508458, 3752824392746, 16359260883466, 71313013661214, 310866547441298 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

Column 2 of A186850.

LINKS

R. H. Hardin, Table of n, a(n) for n = 1..200

FORMULA

Empirical: a(n) = 2*a(n-1) + 4*a(n-2) + 24*a(n-3) + 14*a(n-4) + 3*a(n-5) + 2*a(n-6).

Empirical g.f.: 2*x*(25 + 59*x + 167*x^2 + 91*x^3 + 23*x^4 + 14*x^5) / (1 - 2*x - 4*x^2 - 24*x^3 - 14*x^4 - 3*x^5 - 2*x^6). - Colin Barker, Apr 19 2018

EXAMPLE

Some solutions for 5 X 3:

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

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

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

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

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

CROSSREFS

Cf. A186850.

Sequence in context: A273293 A097371 A179755 * A250527 A251065 A231087

Adjacent sequences:  A186840 A186841 A186842 * A186844 A186845 A186846

KEYWORD

nonn

AUTHOR

R. H. Hardin, Feb 27 2011

STATUS

approved

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Last modified September 17 22:53 EDT 2019. Contains 327147 sequences. (Running on oeis4.)