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A200052 Number of -3..3 arrays x(0..n-1) of n elements with zero sum and elements alternately strictly increasing and strictly decreasing 1
1, 6, 22, 78, 288, 1098, 4224, 16432, 64310, 253692, 1003374, 3992358, 15908668, 63684848, 255153798, 1026057576, 4127971346, 16658240722, 67237254862, 272092306164, 1101134446908, 4466186295698, 18113540529096, 73607652658268 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,2

COMMENTS

Column 3 of A200057

LINKS

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

EXAMPLE

Some solutions for n=6

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

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

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

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

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

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

CROSSREFS

Sequence in context: A032195 A217530 A111566 * A051945 A253070 A255461

Adjacent sequences:  A200049 A200050 A200051 * A200053 A200054 A200055

KEYWORD

nonn

AUTHOR

R. H. Hardin Nov 13 2011

STATUS

approved

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Last modified November 25 09:08 EST 2020. Contains 338623 sequences. (Running on oeis4.)