The On-Line Encyclopedia of Integer Sequences (OEIS)

A199531 revision #5

A199531

Number of -n..n arrays x(0..3) of 4 elements with zero sum and no two consecutive zero elements

12, 72, 212, 464, 860, 1432, 2212, 3232, 4524, 6120, 8052, 10352, 13052, 16184, 19780, 23872, 28492, 33672, 39444, 45840, 52892, 60632, 69092, 78304, 88300, 99112, 110772, 123312, 136764, 151160, 166532, 182912, 200332, 218824, 238420, 259152

(list; graph; refs; listen; history; text; internal format)

OFFSET

1,1

COMMENTS

Row 4 of A199530

LINKS

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

FORMULA

Empirical: a(n) = (16/3)*n^3 + 8*n^2 - (4/3)*n

EXAMPLE

Some solutions for n=5

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

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

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

.-3...-2....2....3....5...-2...-1....1....3....3...-3....1...-3...-5...-3...-5

CROSSREFS

Sequence in context: A340302 A143698 A304164 * A374374 A188660 A047928

Adjacent sequences: A199528 A199529 A199530 * A199532 A199533 A199534

KEYWORD

nonn

AUTHOR

R. H. Hardin Nov 07 2011

STATUS

approved