Three-in-a-row

I learned about the game of three-in-a-row from H. Steinhaus's Mathematical Snapshots. It begins like tic-tac-toe, but with markers instead of Xs and Os. After 6 markers have been placed, players take turns moving their markers one space at a time vertically or horizontally, until someone has three-in-a-row (vertically, horizontally, or diagonally).


In the picture below, the six markers are placed, and it is white's turn. If each player makes their best moves, who wins?

three-in-a-row

More generally, who has the advantage, the first or second player, and what is a winning strategy? Is a stalemate or draw possible? Assuming nobody has won after the first 6 markers are placed, how many ways could black have placed the markers? What variations can you think of for this game?

What other good questions can you come up with?

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