A lattice triangulation is a triangulation all whose vertices are at points with integer coordinates. It is primitive if each triangle is primitive, i.e. of area 1/2. Let f(m,n) be the number of primitive triangulations of an m x n rectangle. In the following files we give the exact values of these numbers for some m,n. The file named mxnf.txt contains a list

{f(m,1), f(m,2), ..... , f(m,n)}

3x600f.txt
4x200f.txt
5x115f.txt
6x74f.txt
7x38f.txt
8x22f.txt
9x12f.txt
10x10f.txt

The C-program for computing f(6,n) mod p, n=1,...,70: tr6x70.c

version 1 (Jan 30, 2022)
version 2 (Jul   06, 2024) 6x50f.txt is replaced by 6x57f.txt
version 3 (Aug   15, 2024) 8x13f.txt is replaced by 8x16f.txt
version 4 (Sep   01, 2024) 7x20f.txt is replaced by 7x28f.txt
version 5 (Sep   12, 2024) 9x9f.txt is replaced by 9x12f.txt
version 6 (Sep   29, 2024) 8x16f.txt is replaced by 8x20f.txt
version 7 (Oct   10, 2024) 10x10f.txt is added
version 8 (Jan   13, 2025) 7x28f.txt is replaced by 7x34f.txt
version 9 (Mar   23, 2025) 6x57f.txt is replaced by 6x70f.txt
version 10 (Aug   22, 2025) 6x70f.txt is replaced by 6x74f.txt
version 11 (Oct   15, 2025) 7x34f.txt is replaced by 7x38f.txt
version 12 (Nov   04, 2025) 8x20f.txt is replaced by 8x22f.txt