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A250920 Number of (n+1) X (1+1) 0..2 arrays with no 2 X 2 subblock having its minimum diagonal element less than its minimum antidiagonal element. 1
58, 344, 2007, 11693, 68160, 397432, 2317569, 13514765, 78810538, 459578476, 2680000719, 15628241161, 91135020168, 531447642196, 3099100611969, 18072193466385, 105386761387818, 614555698316144, 3583739564227927 (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) = 9*a(n-1) - 23*a(n-2) + 29*a(n-3) - 16*a(n-4) + 4*a(n-5).

Empirical g.f.: x*(58 - 178*x + 245*x^2 - 140*x^3 + 36*x^4) / (1 - 9*x + 23*x^2 - 29*x^3 + 16*x^4 - 4*x^5). - Colin Barker, Nov 23 2018

EXAMPLE

Some solutions for n=4:

..2..2....1..0....1..2....1..1....2..0....1..1....1..1....1..2....0..0....2..1

..0..2....2..2....1..2....2..2....0..0....2..1....2..2....0..0....0..0....1..1

..0..1....0..1....0..2....2..2....2..2....2..1....0..2....0..1....2..1....2..1

..0..2....0..0....0..0....2..2....1..1....0..0....0..0....0..1....1..1....0..0

..0..0....1..2....2..0....1..1....0..1....1..0....1..1....0..1....0..2....2..1

CROSSREFS

Column 1 of A250927.

Sequence in context: A027987 A141779 A250927 * A235673 A235730 A235443

Adjacent sequences:  A250917 A250918 A250919 * A250921 A250922 A250923

KEYWORD

nonn

AUTHOR

R. H. Hardin, Nov 28 2014

STATUS

approved

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Last modified September 25 20:01 EDT 2021. Contains 347659 sequences. (Running on oeis4.)