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## 'Tetrahedron Faces' printed from http://nrich.maths.org/

One face of a regular tetrahedron is painted blue and each of
the remaining faces are painted using one of the colours red, green
or yellow.

How many different possibilities are there, if we count those that
just differ by a rotation as the same?

How many different possibilities would there be if the tetrahedron
was irregular?