A199895 - OEIS

A199895

Number of -5..5 arrays x(0..n-1) of n elements with zero sum, and adjacent elements not both strictly positive and not both strictly negative

1, 11, 51, 351, 2031, 13363, 82555, 536967, 3409609, 22163661, 142744843, 930121865, 6040974735, 39482258363, 257848379869, 1690142722447, 11081263427471, 72823380368573, 478876538926483, 3154101346620987

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OFFSET

1,2

COMMENTS

Column 5 of A199898

LINKS

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

EXAMPLE

Some solutions for n=6

..3...-2...-1...-2....0...-3....0...-1....3....4...-2...-2...-2...-5...-3...-2

.-5....2....4....5....4....1...-2....0...-5...-4....3....1....1....0....2....3

..5...-4...-2...-4...-4...-3....3...-5....1....1...-2...-2...-3....2...-5....0

.-3....4....0....3....1....1...-2....2...-4....0....4....0....3....0....3...-5

..1...-3....3...-5...-5....0....0....0....0...-1...-4....3....0....5...-1....4

.-1....3...-4....3....4....4....1....4....5....0....1....0....1...-2....4....0

CROSSREFS

Sequence in context: A168214 A321421 A317021 * A304280 A231386 A191099

Adjacent sequences: A199892 A199893 A199894 * A199896 A199897 A199898

KEYWORD

nonn

AUTHOR

R. H. Hardin Nov 11 2011

STATUS

approved