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A235730 Number of (n+1)X(2+1) 0..1 arrays with the sum of each 2X2 subblock maximum and minimum lexicographically nondecreasing columnwise and nonincreasing rowwise 1
58, 380, 2481, 15963, 102683, 659235, 4232565, 27168327, 174393813, 1119403274, 7185285384, 46121125726, 296043902819, 1900256127618, 12197426714764, 78293240150997, 502551211372960, 3225792130564117, 20705819951262020 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

Column 2 of A235736

LINKS

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

FORMULA

Empirical: a(n) = 9*a(n-1) -11*a(n-2) -56*a(n-3) +133*a(n-4) +13*a(n-5) -220*a(n-6) +73*a(n-7) +147*a(n-8) -64*a(n-9) -45*a(n-10) +19*a(n-11) +5*a(n-12) -2*a(n-13)

EXAMPLE

Some solutions for n=4

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

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

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

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

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

CROSSREFS

Sequence in context: A250927 A250920 A235673 * A235443 A235511 A255684

Adjacent sequences:  A235727 A235728 A235729 * A235731 A235732 A235733

KEYWORD

nonn

AUTHOR

R. H. Hardin, Jan 15 2014

STATUS

approved

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Last modified September 19 00:22 EDT 2021. Contains 347549 sequences. (Running on oeis4.)