Advent calendar 2024
2 December
14 is the smallest even number that cannot be obtained by rolling two 6-sided dice and finding
the product of the numbers rolled.
What is the smallest even number that cannot be obtained by rolling one hundred 100-sided dice
and finding the product of the numbers rolled?
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With two 100-sided dice, it is possible to roll the even numbers from 2 to 200 by rolling a two on one die
and 1 to 100 on the other. It is not possible to roll 202, as 101 is prime so cannot be made by multiplying any numbers less than 101.
With one hundred 100-sided dice, the even numbers from 2 to 200 can still be made (by rolling the two dice as before plus lots of ones).
It is still not possible to roll 202, as 101 is still prime.
