Minimal sibling (reviewed)

The minimal sibling of a number field is a sibling that is minimal with respect to the following quantities considered in order:

• its degree
• the T-number of its Galois group
• the absolute value of its discriminant
• the vector $(a_0, a_1, \ldots, a_{n-1})$ of coefficients of its normalized defining polynomial $x^n+a_{n-1} x^{n-1}+\cdots +a_0$