What is a double factorial (n!!)?

n!! = n × (n−2) × (n−4) × ... down to 1 or 2. E.g. 8!! = 8×6×4×2 = 384.

What about triple factorial (n!!!)?

n!!! = n × (n−3) × (n−6) × ... stepping by 3 until you reach 1, 2, or 3.

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Calculate double factorial (n!!), triple factorial (n!!!), and higher. n!! = n × (n−k) × (n−2k) × ...

Step (2 = double !!, 3 = triple !!!, …)

What is a double factorial (n!!)?: n!! = n × (n−2) × (n−4) × ... down to 1 or 2. E.g. 8!! = 8×6×4×2 = 384.
What about triple factorial (n!!!)?: n!!! = n × (n−3) × (n−6) × ... stepping by 3 until you reach 1, 2, or 3.
Is this tool free?: Yes. All tools on QuickFreeTools are free with no signup.

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