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A188358 T(n,k)=Number of arrangements of n+1 numbers x(i) in -k..k with the sum of x(i)*x(i+1) equal to zero 16
5, 9, 15, 13, 45, 29, 17, 91, 117, 91, 21, 153, 257, 565, 197, 25, 231, 497, 1775, 1953, 627, 29, 325, 749, 4201, 7369, 9153, 1477, 33, 435, 1205, 8051, 22229, 49747, 37269, 4671, 37, 561, 1569, 14477, 45801, 181449, 262925, 173409, 11693, 41, 703, 2161 (list; table; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

Table starts

.....5.......9.......13........17.........21..........25..........29

....15......45.......91.......153........231.........325.........435

....29.....117......257.......497........749........1205........1569

....91.....565.....1775......4201.......8051.......14477.......22583

...197....1953.....7369.....22229......45801......100885......163745

...627....9153....49747....181449.....480363.....1171345.....2295051

..1477...37269...262925...1264985....3882729....11535493....25217201

..4671..173409..1763151..10396729...40629247...136061137...355442823

.11693..766869.10536621..81850801..383541193..1540834589..4602176797

.36487.3589357.70819767.684867741.4033546763.18592832393.65556183495

LINKS

R. H. Hardin, Table of n, a(n) for n = 1..178

EXAMPLE

Some solutions for n=6 k=4

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

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

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

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

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

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

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

CROSSREFS

Row 1 is A016813

Row 2 is A014634

Sequence in context: A115380 A107980 A163161 * A228218 A106503 A160593

Adjacent sequences:  A188355 A188356 A188357 * A188359 A188360 A188361

KEYWORD

nonn,tabl

AUTHOR

R. H. Hardin Mar 28 2011

STATUS

approved

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Last modified April 18 03:01 EDT 2014. Contains 240688 sequences.