Problem 46054. Count trailing zeros in a primorial

• Created by ChrisR
• Appears in Cody Problems in Japanese

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Cody Problem 44068 asked us to count the trailing zeros in a factorial. This problem deals with the primorial. If is the nth prime number, then the primorial # is the product of the prime numbers up to and including . For example, if n = 5, then # = = 2310, which has one trailing zero.

Count the trailing zeros in the primorial #. Because primorials become large quickly, for large n it helps to derive a formula for the number of trailing zeros.*

Please make your code general because I might add more tests later.

See also Cody Problems 46057 "Find the last non-zero digit in a primorial" and 46060 "Identify primorial primes".

*;-)

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Solution Stats

78.57% Correct | 21.43% Incorrect

• 42 Solutions
• 29 Solvers

Last Solution submitted on Feb 26, 2025

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