Some results on the reduced energy of graphs, I


Mirko Lepović




In a recent paper [6], A.Torgašev described all the finite connected graphs whose energy (i. e. the sum of all the positive eigenvalues including also their multiplicities) does not exceed 3. In this paper are described all the connected graphs whose reduced energy, i. e. the sum of absolute values of all the eigenvalues except the largest one, does not exceed 5.