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A184139 Number of nX4 binary arrays with rows and columns in nondecreasing order 1
5, 25, 130, 650, 2942, 11819, 42305, 136564, 402910, 1099694, 2805530, 6748066, 15412437, 33626131, 70430778, 142218719, 277853339, 526833235, 972034814, 1749218190, 3076360192, 5297051455, 8943742419, 14828643610, 24172697276 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

Column 4 of A180985

LINKS

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

FORMULA

Empirical: a(n)=16*a(n-1)-120*a(n-2)+560*a(n-3)-1820*a(n-4)+4368*a(n-5)-8008*a(n-6)+11440*a(n-7)-12870*a(n-8)+11440*a(n-9)-8008*a(n-10)+4368*a(n-11)-1820*a(n-12)+560*a(n-13)-120*a(n-14)+16*a(n-15)-a(n-16) (=polynomial degree 15)

EXAMPLE

Some solutions for 3X4

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

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

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

CROSSREFS

Sequence in context: A060928 A002002 A182626 * A102893 A094602 A207834

Adjacent sequences:  A184136 A184137 A184138 * A184140 A184141 A184142

KEYWORD

nonn

AUTHOR

R. H. Hardin Jan 09 2011

STATUS

approved

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Last modified August 22 02:44 EDT 2019. Contains 326169 sequences. (Running on oeis4.)