APPROXIMATION OF VISCOSITY SOLUTIONS OF ELLIPTIC PARTIAL-DIFFERENTIALEQUATIONS ON MINIMAL GRIDS - APPROXIMATION TO ORTHOGONAL BASES IN R(N) BY ORTHOGONAL BASES WITH INTEGER COORDINATES - APPENDIX

In the Appendix it is shown that given N > 1, an orthogonal basis phi( 1),...,phi(n), of R(n) where n greater than or equal to 4 can be appro ximated by an orthogonal basis a(1),..., a(n) with integer components such that the angle between phi(i) and a(i) is at most 1/N (i = 1,..., n), and a(1),...,a(n) have norms much less than N-2n-4.