  This paper considers a dilute Ising ferromangnet with annealed vacancies and
attractive biquadratic interactions. Phase diagrams have been calculated while
varying the temperature and concentration of annealed vacancies in the system
while maintaining constant, attractive biquadratic couplings. These results
have been produced using renormalization group analysis with a hierarchical
lattice. Critical exponents have been calculated and each basin of attraction
interpreted.
