Nonnegative matrices having same nonnegative moore-penrose and group inverses
S. K. Jain, Vaibhava Goel, Edward K. Kwak · Linear and Multilinear Algebra · 1979
Nonnegative matrices A whose Moore-Penrose generalized inverse A+ is nonnegative and has any one of the three equivalent properties (i) AA+ = A+ A (ii) A+ = A, the group inverse, (iii) A+ = p(A), some polynomial in A with scalar coefficients, are characterized. This characterization generalizes known results on nonnegative matrices Awhose Moore-Penrose generalized inverse is equal to some power of A.