(adsbygoogle = window.adsbygoogle || []).push({}); The problem statement

Suppose you have n beads, each with a different color. You need to string these beads into a necklace. How many distinct necklaces can you make? (A necklace flipped over remains the same and does not count as a distinct necklace.)

The attempt at a solution

I decided to figure out the first couple necklaces:

n=3: 3 beads can only be arranged 1 distinct way that cant be duplicated by flipping or rotating.

n=4: 4 beads can be arranged 3 ways.

Browsing the internet, i found some fairly complicated equations that I didn't really understand, but I found one for N beads with K different colors, which simplified down to (n-1)! / 2 for N=K. I tried this out for n=3 and 4, and it worked for both of those, but that's far from proof that it works beyond that.

What i really want to know is if this formula is correct, and if not, a way of thinking about this problem that will lead me down the path to a correct formula.

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# Counting Unique Necklaces

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