I bet this on the first go, without thinking of an in-depth heuristic. Maybe I was lucky, but it doesn't seem to hard.
I struggled with this version, which is kind of similar: http://joezeng.github.io/144/
I struggled with this version, which is kind of similar: http://joezeng.github.io/144/
144=3 x 48 ; 48=3 x 16
16 is 'easy' to create - if you can avoid creating any three-pairs.
The trick of this game is that you can have 3,4,5 pairs. There may be some ways to choose 4 and 5 pairs along with the easier 2 and 3 pairs to win it - my efforts so far with the simple strategy produced two 48 pairs, and a seemingly random chance at producing an elusive third 48th pair, so any solution I would think would be considerably more difficult, if one exists at all.
243 243 243 x x
81 81 81 x x
27 27 27 x x
9 9 9 x x
3 3 3 x x