A192693 Number of 1X6 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 6-vectors with total modulus squared not more than 2*n^2, ignoring vector and component permutations).
2, 9, 28, 78, 171, 350, 650, 1142, 1868, 2949, 4454, 6554, 9361, 13071, 17829, 23929, 31576, 41080, 52705, 66899, 83871, 104326, 128432, 156793, 190022, 228672, 273250, 324752, 383434, 450569, 526647, 612832, 709667, 818736, 940570, 1076447, 1227802
Offset: 1
Keywords
Examples
Some solutions for 1X6 <= 2*4^2 .-3.-2..0..0..2..3...-3.-1..0..0..2..2...-3.-1.-1.-1..3..3...-3.-2.-1..1..2..3
Links
- R. H. Hardin, Table of n, a(n) for n = 1..200
Comments