On the diagonals of rational functions: the minimal number of variables
(unabridged version)
On the diagonals of rational functions: the minimal number of variables
(unabridged version)
From some observations on the linear differential operators occurring in the Lattice Green function of the d-dimensional face centred and simple cubic lattices, and on the linear differential operators occurring in the n-particle contributions to the magnetic susceptibility of the square Ising model, we forward some conjectures on the diagonals …