Three applications of the Siegel mass formula
arXiv:1811.12828
Abstract
We present three applications of the Siegel mass formula. First we estimate the number of solutions of a quadratic system of equations. We also include estimates for the distribution of lattice points on caps of four dimensional spheres and for the number of non-congruent lattice tetrahedra.
Error in the proof of Theorem 2.1 has been corrected. arXiv admin note: substantial text overlap with arXiv:1312.1714