It looks like the 'b' value is the number of sections the curve is divided into. Also, I noticed that when the value of 'a' is even, the resulting graph is open and when 'a' is odd, the graph is closed.

Let's try a few more and see if this is the case:

When a = 1 and b = 3, the following graph results:

**
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*Notice: the curve is closed and is split into 3 sections.

When a = 1 and b= 4, the following graph results:

**
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*Notice: the curve is closed and is split into 4 sections.

When a = 3 and b = 1, the following graph results:

**
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*Notice: the curve is closed and is split into 3 sections.

When a = 4 and b = 1, the following graph results:

**
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*Notice: the curve is open ...

**OH ... WELL! My
observation was WRONG!!!**