A rational approximation to 〈VV−AA〉〈VV−AA〉 and its O(p6)O(p6) low-energy constant

Using a sequence of rational approximants and the large-NcNc limit of QCD, we estimate the value of the low-energy constant C87C87 which appears in the Lagrangian of Chiral Perturbation Theory at O(p6)O(p6).