A194193 Square array read by antidiagonals downwards: T(n,k) = number of ways to arrange k indistinguishable points on an n X n square grid so that no three points are collinear at any angle.
1, 0, 4, 0, 6, 9, 0, 4, 36, 16, 0, 1, 76, 120, 25, 0, 0, 78, 516, 300, 36, 0, 0, 28, 1278, 2148, 630, 49, 0, 0, 2, 1668, 9498, 6768, 1176, 64, 0, 0, 0, 998, 25052, 47331, 17600, 2016, 81, 0, 0, 0, 204, 36698, 215448, 175952, 40120, 3240, 100, 0, 0, 0, 11, 26700, 620210
Offset: 1
Examples
Table starts: ...1.....0.......0........0..........0...........0............0............0 ...4.....6.......4........1..........0...........0............0............0 ...9....36......76.......78.........28...........2............0............0 ..16...120.....516.....1278.......1668.........998..........204...........11 ..25...300....2148.....9498......25052.......36698........26700.........8242 ..36...630....6768....47331.....215448......620210......1073076......1035097 ..49..1176...17600...175952....1189868.....5367308.....15657764.....28228158 ..64..2016...40120...545764....5199888....34678364....159413700....491910848 ..81..3240...82608..1461672...18520572...169259212...1108580092...5122725512 .100..4950..157252..3507553...56978440...682686652...6030207624..38914424892 .121..7260..280988..7701638..155627304..2356999994..26852315940.229093733030 .144.10296..477012.15773526..388897892..7294368210.104865006648 .169.14196..775172.30375194..894254904.20227526910 .196.19110.1214768.55695587.1932504496 .225.25200.1844512.97777392 .256.32640.2725000 ... Some solutions for n=4, k=4: ..0..0..1..0....0..0..0..0....0..0..0..0....0..0..1..0....1..0..0..0 ..1..0..0..0....1..0..0..0....0..0..1..0....1..0..0..0....0..0..0..1 ..0..0..0..0....0..1..0..1....1..0..1..0....1..0..0..0....0..0..0..1 ..0..0..1..1....0..1..0..0....0..1..0..0....0..0..0..1....1..0..0..0
Links
- R. H. Hardin and Heinrich Ludwig, Table of n, a(n) for n = 1..199, (first 181 terms from R. H. Hardin)
Comments