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A235550 Number of (n+1)X(2+1) 0..1 arrays with the sum of each 2X2 subblock two extreme terms minus its two median terms lexicographically nondecreasing rowwise and columnwise 1
46, 202, 814, 2878, 9320, 27731, 77606, 205571, 522118, 1277701, 3035682, 7026779, 15922886, 35411253, 77537074, 167468443, 357585774, 755895685, 1584418882, 3296648763, 6816697174, 14019547045, 28702737170, 58535302827, 118984571742 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

Column 2 of A235555

LINKS

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

FORMULA

Empirical: a(n) = 4*a(n-1) +9*a(n-2) -54*a(n-3) -15*a(n-4) +312*a(n-5) -133*a(n-6) -998*a(n-7) +840*a(n-8) +1896*a(n-9) -2268*a(n-10) -2088*a(n-11) +3472*a(n-12) +1088*a(n-13) -3120*a(n-14) +96*a(n-15) +1536*a(n-16) -384*a(n-17) -320*a(n-18) +128*a(n-19)

EXAMPLE

Some solutions for n=5

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

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

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

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

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

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

CROSSREFS

Sequence in context: A192850 A211334 A160334 * A083358 A254229 A234161

Adjacent sequences:  A235547 A235548 A235549 * A235551 A235552 A235553

KEYWORD

nonn

AUTHOR

R. H. Hardin, Jan 12 2014

STATUS

approved

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Last modified September 18 12:05 EDT 2021. Contains 347527 sequences. (Running on oeis4.)