

A192705


Number of 5X2 integer matrices with each row summing to zero, row elements in nondecreasing order, rows in lexicographically nondecreasing order, and the sum of squares of the elements <= 2*n^2 (number of collections of 5 zerosum 2vectors with total modulus squared not more than 2*n^2, ignoring vector and component permutations)


1



2, 6, 14, 29, 56, 101, 166, 267, 407, 604, 865, 1211, 1659, 2236, 2956, 3861, 4949, 6299, 7906, 9849, 12120, 14817, 17958, 21641, 25859, 30753, 36318, 42732, 49917, 58116, 67296, 77693, 89219, 102175, 116527, 132515, 150117, 169602, 191013, 214662
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OFFSET

1,1


COMMENTS

Column (5,2,n) of A192710


LINKS

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


EXAMPLE

Some solutions for 5X2 <= 2*4^2
.3..3...2..2...2..2...1..1...1..1...2..2...3..3...3..3...3..3...2..2
.1..1...1..1...2..2...1..1...1..1...2..2...1..1....0..0...1..1...2..2
.1..1...1..1...1..1....0..0...1..1...2..2...1..1....0..0....0..0...2..2
.1..1....0..0...1..1....0..0....0..0...2..2...1..1....0..0....0..0....0..0
.1..1....0..0...1..1....0..0....0..0....0..0....0..0....0..0....0..0....0..0


CROSSREFS

Sequence in context: A321027 A214907 A169948 * A123991 A112511 A063452
Adjacent sequences: A192702 A192703 A192704 * A192706 A192707 A192708


KEYWORD

nonn


AUTHOR

R. H. Hardin Jul 07 2011


STATUS

approved



