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A202042 Number of zero-sum nX3 -1..1 arrays with every element unequal to at most two horizontal and vertical neighbors 1
7, 73, 415, 2921, 19541, 149149, 1067983, 8193025, 60897081, 469758219, 3566405667, 27631630057, 212463113105, 1652463728885, 12810745435213, 99982282638169, 779490730807285, 6102033983822007, 47767263490283739 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

Column 3 of A202047

LINKS

R. H. Hardin, Table of n, a(n) for n = 1..67

EXAMPLE

Some solutions for n=5

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

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

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

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

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

CROSSREFS

Sequence in context: A175205 A027017 A076106 * A294291 A318688 A117982

Adjacent sequences:  A202039 A202040 A202041 * A202043 A202044 A202045

KEYWORD

nonn

AUTHOR

R. H. Hardin Dec 10 2011

STATUS

approved

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Last modified August 12 22:46 EDT 2022. Contains 356077 sequences. (Running on oeis4.)