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A283100 T(n,k)=Number of nXk 0..1 arrays with no 1 equal to more than one of its horizontal and vertical neighbors, with the exception of exactly two elements. 8
0, 0, 0, 0, 0, 0, 1, 6, 6, 1, 2, 28, 72, 28, 2, 5, 142, 600, 600, 142, 5, 13, 606, 4607, 8536, 4607, 606, 13, 29, 2458, 31669, 107007, 107007, 31669, 2458, 29, 65, 9520, 208949, 1237504, 2231690, 1237504, 208949, 9520, 65, 143, 35678, 1324269, 13563911 (list; table; graph; refs; listen; history; text; internal format)
OFFSET

1,8

COMMENTS

Table starts

..0.....0.......0..........1............2..............5...............13

..0.....0.......6.........28..........142............606.............2458

..0.....6......72........600.........4607..........31669...........208949

..1....28.....600.......8536.......107007........1237504.........13563911

..2...142....4607.....107007......2231690.......42681282........774403237

..5...606...31669....1237504.....42681282.....1354321470......40737147156

.13..2458..208949...13563911....774403237....40737147156....2028744947006

.29..9520.1324269..142827186..13508097744..1177012522158...97051820977159

.65.35678.8152245.1460284133.228643318057.32993790452893.4503103658479576

LINKS

R. H. Hardin, Table of n, a(n) for n = 1..220

FORMULA

Empirical for column k:

k=1: a(n) = 3*a(n-1) -2*a(n-3) -6*a(n-4) +4*a(n-6) +6*a(n-7) +3*a(n-8) +a(n-9)

k=2: [order 12]

k=3: [order 27]

k=4: [order 46]

EXAMPLE

Some solutions for n=4 k=4

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

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

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

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

CROSSREFS

Column 1 is A282831.

Sequence in context: A322622 A176565 A176567 * A065493 A133890 A248059

Adjacent sequences:  A283097 A283098 A283099 * A283101 A283102 A283103

KEYWORD

nonn,tabl

AUTHOR

R. H. Hardin, Feb 28 2017

STATUS

approved

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Last modified January 26 23:05 EST 2020. Contains 331289 sequences. (Running on oeis4.)