Stirling number Identities and High energy String Scatterings

We use Stirling number identities developed recently in number theory to show that ratios among high energy string scattering amplitudes in the fixed angle regime can be extracted from the Kummer function of the second kind. This result not only brings an interesting bridge between string theory and combinatoric number theory but also sheds light on the understanding of algebraic structure of high energy stringy symmetry.