How many necklace of 12 beads, each can be made from 18 beads of various colours?

Explanation

To solve the problem of how many necklaces of 12 beads can be made from 18 beads of various colors, we can follow these steps:

### Step 1: Understand the Problem
We need to find the number of distinct arrangements of 12 beads selected from 18 beads, considering that the arrangements are circular and indistinguishable when flipped (clockwise vs. anti-clockwise).

### Step 2: Circular Permutations
For circular arrangements, the formula for permutations is given by:
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