Find conditions for all chips to become of the same color in this game

There are a white, b black, and c red chips on a table. In one step, you may choose two chips of different colors and replace each one by a chip of the third color. Find conditions for all chips to become of the same color. Suppose you have initially $13$ white $15$ black and $17$ red chips. Can all chips become of the same color? What states can be reached from these numbers?

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