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A201885 Number of zero-sum nX2 -2..2 arrays with every element equal to at least one horizontal or vertical neighbor 1
1, 9, 63, 413, 3293, 25123, 196811, 1610765, 13183301, 109772649, 924269015, 7845330131, 67157103399, 578601709251, 5012862231269, 43640547493913, 381459159995789, 3345900096556721, 29435197443234979, 259612374333413841 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,2

COMMENTS

Column 2 of A201888

LINKS

R. H. Hardin, Table of n, a(n) for n = 1..128

EXAMPLE

Some solutions for n=6

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

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

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

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

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

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

CROSSREFS

Sequence in context: A016137 A230547 A339786 * A225964 A037508 A037691

Adjacent sequences:  A201882 A201883 A201884 * A201886 A201887 A201888

KEYWORD

nonn

AUTHOR

R. H. Hardin Dec 06 2011

STATUS

approved

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Last modified June 14 17:31 EDT 2021. Contains 345037 sequences. (Running on oeis4.)