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A202506 Number of zero-sum -3..3 arrays of n elements with first through third differences also in -3..3 1
1, 3, 15, 29, 95, 255, 747, 2215, 6649, 19967, 60145, 182003, 554625, 1691547, 5175093, 15875649, 48789933, 150258301, 463501341, 1431832723, 4429155217, 13716674493, 42524970155, 131966196475, 409893633219, 1274208141011 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,2

COMMENTS

Column 3 of A202511

LINKS

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

EXAMPLE

Some solutions for n=7

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

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

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

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

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

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

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

CROSSREFS

Sequence in context: A147344 A201434 A308385 * A053519 A039666 A020493

Adjacent sequences:  A202503 A202504 A202505 * A202507 A202508 A202509

KEYWORD

nonn

AUTHOR

R. H. Hardin Dec 20 2011

STATUS

approved

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Last modified April 3 04:11 EDT 2020. Contains 333195 sequences. (Running on oeis4.)