What is the name of the circle that is tangent to three mutually-tangent circles centered at the vertices of a triangle?

geometry euclidean-geometry soddy-circles

I want some information about the little 'tangent circle', but I don't have its name to search for it in the internet. What is it called?

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Solution 1:

I think that's the Inner Soddy Circle.

Solution 2:

I think that (inner) Soddy circle is what you want.

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