CONCENTRATION OF THE MULTICRITICAL POINTS IN THE + -J ISING-MODELS/

For the +/- J Ising models, it is proved that p(c) (the concentration of + J bonds) of the multicritical point in the model A does not excee d that in the model B (p(c, A) less-than-or-equal-to p(c, B) when the model A is obtained from the model B by adding bonds, each of which ta kes + J or - J with the same probability weight as in the model B. The proof holds for any lattice structure, dimension of the lattice and r ange of the interactions.