Thank you very much for this great course of point registration. I found a matrix notation after the following line
Solving this small system gives us our translation vector and the linearized rotation . If we simply assign

seemed to be wrong. Correctly, it should be the same as the first occurrence, namely some of a_2 should be replaced by a_3 like:

Thank you very much for this great course of point registration. I found a matrix notation after the following line
seemed to be wrong. Correctly, it should be the same as the first occurrence, namely some of
a_2should be replaced bya_3like: