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The smallest number divisible by everything up to 20

numberslcmprime-factors

What is the smallest positive whole number that is divisible by each of the numbers 1, 2, 3, ..., 20?

Explain the method, and say why simply multiplying 1 to 20 together gives something far too big.

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For each prime up to 20, find the highest power of that prime that is at most 20. Multiply those powers together.

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