A201886 - OEIS

A201886

Number of zero-sum nX3 -2..2 arrays with every element equal to at least one horizontal or vertical neighbor

1, 63, 765, 26003, 559115, 16513425, 435630965, 12576072219, 355197660509, 10318921933459, 299385686951737, 8776646594694357, 257891661687979323, 7614010950576116449, 225337048658653360699, 6687122593012508859001

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OFFSET

1,2

COMMENTS

Column 3 of A201888

LINKS

R. H. Hardin, Table of n, a(n) for n = 1..32

EXAMPLE

Some solutions for n=4

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

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

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

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

CROSSREFS

Sequence in context: A024004 A284927 A321545 * A232794 A091027 A112494

Adjacent sequences: A201883 A201884 A201885 * A201887 A201888 A201889

KEYWORD

nonn

AUTHOR

R. H. Hardin Dec 06 2011

STATUS

approved