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A199826 Number of -2..2 arrays x(0..n+1) of n+2 elements with zero sum and no two neighbors summing to zero 1
10, 40, 114, 426, 1650, 6126, 23206, 88636, 337866, 1295566, 4992364, 19269156, 74529210, 288954786, 1122363984, 4366362420, 17011617426, 66365823648, 259213619826, 1013542247970, 3966939195402, 15540399135516, 60929935280508 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

Column 2 of A199832

LINKS

R. H. Hardin, Table of n, a(n) for n = 1..200

EXAMPLE

Some solutions for n=3

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

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

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

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

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

CROSSREFS

Sequence in context: A063490 A251121 A002419 * A227056 A027981 A013977

Adjacent sequences:  A199823 A199824 A199825 * A199827 A199828 A199829

KEYWORD

nonn

AUTHOR

R. H. Hardin Nov 11 2011

STATUS

approved

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Last modified February 24 11:12 EST 2018. Contains 299603 sequences. (Running on oeis4.)