`We evaluate the invariant forms of the neutrino mass matrices which arise from the seesaw mechanism with heavy Majorana mass matrices subject to texture zero under a`

cyclic permutation. From eight possible patterns of the heavy Majorana neutrino mass matrices, we found that there is no heavy Majorana neutrino mass matrix

invariant in form under a cyclic permutation. But, by imposing an additional assumption that at least one of the 2x2 sub-matrices of the heavy Majorana neutrino

mass matrix inverse has zero determinant, we found that two of the heavy Majorana neutrino mass matrices have to be invariant under a cyclic permutation. One of

these two invariant heavy Majorana neutrino mass matrix can be used to explain the neutrino mixing phenomena for both solar and atmospheric neutrinos qualitatively.

Asan Damanik, Mirza Satriawan, Arief Hermanto and Pramudita Anggraita (J. Theor.Comput. Stud. 8 (2008) 0102)