10! = 10×9×8×7×6×5×4×3×2×1 = 5×2×3×3×2×2×2×7×3×2×5×2×2×3×2×1 = 7×5×5×3×3×3×3×2×2×2×2×2×2×2×2×1 So either m or n must be >= 7 = 7!×5×3×3×2×2×2×2×1 = 7! ×6×5×4×3×2×1 = 7!×6! m=7, n=6 m×n=42
edit: how to not spoil the puzzle for others?
OMG! You beat me by less than a minute.
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Nice! It’s always 42!
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And yes, 6 and 7 are one of the 3 possible answer sets. Good job!
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10, 1 10, 0
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Yes, this completes the answer sheet. 0! = 1, hence the third solution.
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edit: how to not spoil the puzzle for others?
I suggested a feature for this yesterday: https://github.com/stackernews/stacker.news/issues/1422
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