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A201797 Number of zero-sum nX2 -2..2 arrays with every element unequal to at most two horizontal and vertical neighbors 1
5, 85, 455, 3617, 28625, 235827, 1972115, 16703881, 142672901, 1226999941, 10610923603, 92180196507, 803840798219, 7032319990027, 61691173120353, 542479698511869, 4780243712781261, 42200307665852185, 373156481784589911 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

Column 2 of A201803

LINKS

R. H. Hardin, Table of n, a(n) for n = 1..126

EXAMPLE

Some solutions for n=5

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

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

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

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

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

CROSSREFS

Sequence in context: A137083 A198586 A121290 * A012743 A139744 A195156

Adjacent sequences:  A201794 A201795 A201796 * A201798 A201799 A201800

KEYWORD

nonn

AUTHOR

R. H. Hardin Dec 05 2011

STATUS

approved

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Last modified May 11 18:21 EDT 2021. Contains 343808 sequences. (Running on oeis4.)