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A223120 Number of nX2 0..2 arrays with no more than floor(nX2/2) elements equal to at least one horizontal or antidiagonal neighbor, with new values introduced in row major 0..2 order 1
1, 10, 72, 664, 5376, 47968, 406400, 3585408, 30987264, 272565760, 2378450944, 20921604096, 183506403328, 1615798558720, 14215745994752, 125323120574464, 1104802314190848, 9750937675890688, 86084069811027968, 760548158573379584 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,2

COMMENTS

Column 2 of A223126

LINKS

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

EXAMPLE

Some solutions for n=3

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

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

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

CROSSREFS

Sequence in context: A155606 A181671 A058111 * A240275 A181402 A003366

Adjacent sequences:  A223117 A223118 A223119 * A223121 A223122 A223123

KEYWORD

nonn

AUTHOR

R. H. Hardin Mar 15 2013

STATUS

approved

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Last modified December 1 22:24 EST 2020. Contains 338858 sequences. (Running on oeis4.)