  We use the spectrum of {42}Sc as input to calculate wave functions and energy
levels of all nuclei in the single-j-shell model with j equal to f_{7/2}. The
value of these results for educational purposes is pointed out. Also new
insights emerge. For example, it is noted that for the (Z=4,N=4) nucleus
{48}Cr, a good quantum number comes out: (-1)^{(v_p+v_n)/2}, where v_p and v_n
are the seniority quantum numbers of the protons and neutrons, respectively.
