OFFSET
2,5
COMMENTS
T(n,n) = T(n,n-1) because all grid points with m = n lie on a side of the triangle and thus not strictly inside.
EXAMPLE
The triangle begins:
0;
1, 1;
1, 3, 3;
2, 4, 6, 6;
2, 4, 7, 10, 10;
3, 6, 9, 12, 15, 15;
3, 7, 9, 14, 17, 21, 21;
4, 7, 12, 16, 19, 24, 28, 28;
4, 9, 13, 16, 22, 27, 31, 36, 36;
5, 10, 15, 20, 25, 30, 35, 40, 45, 45;
5, 10, 15, 22, 25, 33, 37, 43, 49, 55, 55
PROG
(PARI) T(n, m) = sum(i=1, n-1, sum(j=1, m-1, (i/j > n/m))); \\ Michel Marcus, Jun 07 2022
CROSSREFS
KEYWORD
AUTHOR
Hugo Pfoertner, Jun 06 2022
STATUS
approved