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A201884 Number of zero-sum nX1 -2..2 arrays with every element equal to at least one horizontal or vertical neighbor 1
0, 1, 1, 5, 1, 23, 25, 97, 155, 553, 893, 2945, 5721, 16499, 34509, 96903, 211929, 571639, 1310827, 3446631, 8106415, 21036009, 50484447, 129556711, 315618625, 804915729, 1980809241, 5032086931, 12478845269, 31624865741, 78861551727 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,4

COMMENTS

Column 1 of A201888

LINKS

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

EXAMPLE

Some solutions for n=8

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

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

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

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

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

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

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

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

CROSSREFS

Sequence in context: A167572 A147476 A146675 * A294138 A207824 A179900

Adjacent sequences: A201881 A201882 A201883 * A201885 A201886 A201887

KEYWORD

nonn

AUTHOR

R. H. Hardin Dec 06 2011

STATUS

approved

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Last modified November 28 20:13 EST 2022. Contains 358421 sequences. (Running on oeis4.)