A192696 Number of 1X9 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 1 zero-sum 9-vectors with total modulus squared not more than 2*n^2, ignoring vector and component permutations).

2, 10, 48, 185, 577, 1570, 3840, 8577, 17690, 34551, 63830, 112942, 192361, 317003, 506670, 789958, 1201985, 1791493, 2619745, 3765999, 5326330, 7428899, 10220081, 13894828, 18669185, 24830564, 32689442, 42659878, 55175883, 70815315, 90176720

Offset

1,1

Comments

Column (1,9,n) of A192710

Links

R. H. Hardin, Table of n, a(n) for n = 1..68

Example

Some solutions for 1X9 <= 2*4^2
.-3.-2..0..0..1..1..1..1..1...-2.-2.-1.-1.-1..0..1..3..3

Crossrefs

Sequence in context: A009316 A116194 A054138 * A387764 A181296 A239073

Adjacent sequences: A192693 A192694 A192695 * A192697 A192698 A192699

Keyword

nonn

Author

R. H. Hardin, Jul 07 2011

Status

approved