A188361 - OEIS

A188361

Number of arrangements of 6 numbers x(i) in -n..n with the sum of x(i)*x(i+1) equal to zero

197, 1953, 7369, 22229, 45801, 100885, 163745, 283893, 438373, 678617, 911709, 1386673, 1772141, 2399001, 3175561, 4167365, 5010369, 6549541, 7719713, 9789981, 11867065, 14232893, 16279425, 20224801

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OFFSET

1,1

COMMENTS

Row 5 of A188358

LINKS

Table of n, a(n) for n=1..24.

EXAMPLE

Some solutions for n=4

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

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

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

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

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

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

CROSSREFS

Sequence in context: A031706 A201256 A231462 * A329107 A097733 A114050

Adjacent sequences: A188358 A188359 A188360 * A188362 A188363 A188364

KEYWORD

nonn

AUTHOR

R. H. Hardin Mar 28 2011

STATUS

approved