The Erdos number, honoring the late Hungarian mathematician Paul Erdos, is a way of describing the “collaborative distance” between a person and Erdos, as measured by authorship of mathematical papers.
In order to be assigned an Erdos number, an author must co-write a mathematical paper with an author with a finite Erdos number. Paul Erdos is the one person having an Erdos number of zero. If the lowest Erdos number of a coauthor is k, then the author’s Erdos number is k + 1.
Marco Cagnazzo has an Erdos number less or equal to five through the following connections:
1) P. Erdos, A. L. Rubin and H. Taylor. “Choosability in graphs”, in Proc. West Coast Conf. on Combinatorics, Graph Theory and Computing, Congressus Numerantium XXVI: 125–157 (1979).
2) A. Rubin and J. R. Klauder. “The Comparative Roles of Connected and Disconnected Trajectories in the Evaluation of the Semiclassical Coherent-State Propagator”, Annals of Physics 241, 212234 (1995).
3) I. Daubechies and J.R. Klauder. “Constructing measures for path integrals”, J. Math. Phys., 23 (10), pp. 1806-1822, 1982.
4) M. Antonini, M. Barlaud, P. Mathieu, and I. Daubechies. “Image coding using wavelet transform”, IEEE Trans. Image Proc., 1 (2), pp. 205-220, 1992.
5) M. Cagnazzo, F. Castaldo, T. Andre, M. Antonini, M. Barlaud. “Optimal Motion Estimation for Wavelet Video Coding”, IEEE Transaction on Circuits and Systems for Video Technology, vol. 17, no. 7, July 2007, pp 907-911.