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2024 ways to place domino Indonesia Regional

Source: 2024 Indonesia Regional MO Essay Problem 2

May 6, 2024
dominocombinatoricsChessboardboardBoardsIndonesiaRMO

Problem Statement

Given an n×nn \times n board which is divided into n2n^2 squares of size 1×11 \times 1, all of which are white. Then, Aqua selects several squares from this board and colors them black. Ruby then places exactly one 1×21\times 2 domino on the board, so that the domino covers exactly two squares on the board. Ruby can rotate the domino into a 2×12\times 1 domino.
After Aqua colors, it turns out there are exactly 20242024 ways for Ruby to place a domino on the board so that it covers exactly 11 black square and 11 white square.
Determine the smallest possible value of nn so that Aqua and Ruby can do this.
Proposed by Muhammad Afifurrahman, Indonesia