A pair of mathematicians solved a legendary question about the proportion of vertices in a graph with an odd number of connections.

Hossein Abdollahzadeh Ahangar ᵃ, Saeed Kosari ᵇ, Seyed Mahmoud Sheikholeslami ᵇ, Lutz Volkmann ᶜ, Graphs with Large Geodetic Number, Filomat, Vol. 29, No. 6 (2015), pp. 1361-1368 ...

Abstract. In the present paper we are interested in the study of the distance Laplacian eigenvalues of a connected graph with fixed order n and chromatic number χ. We prove lower bounds on the ...