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T(n,k) =Number number of ways to arrange k indistinguishable points on an nXnXn n X n X n triangular grid so that no three points are collinear at any angle.
Some solutions for n=4 , k=4:
R. H. Hardin , Aug 17 2011
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editing
_R. H. Hardin (rhhardin(AT)att.net) _ Aug 17 2011
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R. H. Hardin, <a href="/A194136/b194136.txt">Table of n, a(n) for n = 1..267</a>
allocated for Ron HardinT(n,k)=Number of ways to arrange k indistinguishable points on an nXnXn triangular grid so that no three points are collinear at any angle
1, 0, 3, 0, 3, 6, 0, 1, 15, 10, 0, 0, 17, 45, 15, 0, 0, 6, 105, 105, 21, 0, 0, 0, 114, 407, 210, 28, 0, 0, 0, 39, 843, 1216, 378, 36, 0, 0, 0, 1, 792, 4122, 3036, 630, 45, 0, 0, 0, 0, 244, 7587, 14988, 6696, 990, 55, 0, 0, 0, 0, 9, 6480, 43836, 45414, 13428, 1485, 66, 0, 0, 0, 0
1,3
Table starts
...1....0......0.......0.........0..........0...........0............0
...3....3......1.......0.........0..........0...........0............0
...6...15.....17.......6.........0..........0...........0............0
..10...45....105.....114........39..........1...........0............0
..15..105....407.....843.......792........244...........9............0
..21..210...1216....4122......7587.......6480........1875...........78
..28..378...3036...14988.....43836......69798.......52323........14268
..36..630...6696...45414....194013.....496198......695616.......464934
..45..990..13428..119340....696765....2595897.....5840088......7278867
..55.1485..25005..281442...2145687...10912452....35715529.....71089536
..66.2145..43861..608616...5851044...38739354...172520643....496946172
..78.3003..73277.1228812..14546412..121694240...708871152...2796515883
..91.4095.117471.2338779..33347130..342722071..2517687856..12966188538
.105.5460.181880.4240284..71662911..887407361..8023634766..52262929401
.120.7140.273268.7371414.145616964.2136513884.23292994812.187041426756
Some solutions for n=4 k=4
.....1........0........1........0........0........0........0........0
....0.0......1.1......1.0......0.1......1.1......1.0......1.1......0.1
...0.1.0....0.0.1....0.0.0....1.0.0....1.0.0....1.0.1....1.1.0....1.1.0
..1.0.0.1..1.0.0.0..0.1.1.0..0.1.0.1..0.0.1.0..0.0.1.0..0.0.0.0..0.0.0.1
allocated
nonn,tabl
R. H. Hardin (rhhardin(AT)att.net) Aug 17 2011
approved
editing
allocated for Ron Hardin
allocated
approved