Minimal No-3-in-line on a hexagon.

[Ed Pegg]

I decided to look at the hexagonal version of https://oeis.org/A277433 
Martin Gardner's minimal no-3-in-a-line problem, all slopes version.  

Not shown: the unique 5-point solution for the side-3 hexagon.  I've turned 
this into a Martin Gardner style puzzle.  

Remove three cells each from two opposite corners of a 5×5 grid.
On this grid, place five counters such that adding one more counter on any vacant square will produce three in a line. The solution is unique (barring rotations and reflections)

🟨🟨🟨🟫🟫
🟨🟨🟨🟨🟫
🟨🟨🟨🟨🟨
🟫🟨🟨🟨🟨
🟫🟫🟨🟨🟨 

Here are my best solutions for higher orders. 

 

[Ed Pegg]

Here's the unique answer for the side 3 hexagon -- a glider configuration.

▢▣▢▤▤
▢▣▣▢▤
▣▢▣▢▢
▤▢▢▢▢
▤▤▢▢▢  

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