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A199894 Number of -4..4 arrays x(0..n-1) of n elements with zero sum, and adjacent elements not both strictly positive and not both strictly negative 1
1, 9, 37, 209, 1043, 5725, 30199, 164993, 890299, 4877477, 26632013, 146499083, 805700567, 4449304857, 24590147861, 136249639279, 755738351775, 4199211521573, 23357174342185, 130088542750275, 725223072283995 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,2

COMMENTS

Column 4 of A199898

LINKS

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

EXAMPLE

Some solutions for n=6

.-2....1....0...-2....3....3....1....3...-2....0....3...-1....1....2....4....1

..3....0....4....0....0...-3...-1....0....2...-2....0....0...-1...-3...-2...-1

..0....0...-4....0...-2....0....1...-4...-1....0....0...-1....4....3....1....4

..1...-4....3....0....1...-3...-2....2....0....2....0....2...-2....0...-2....0

.-2....0...-3...-2...-2....3....2...-4....1....0....1...-4....2....2....2...-4

..0....3....0....4....0....0...-1....3....0....0...-4....4...-4...-4...-3....0

CROSSREFS

Sequence in context: A232250 A201441 A183327 * A232258 A026686 A076174

Adjacent sequences:  A199891 A199892 A199893 * A199895 A199896 A199897

KEYWORD

nonn

AUTHOR

R. H. Hardin Nov 11 2011

STATUS

approved

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Last modified February 24 03:22 EST 2020. Contains 332195 sequences. (Running on oeis4.)