Formulas for the number of gridlines
: Ernvall-Hytonen AM, Matomaki K, Haukkanen P, Merikoski JK
Publisher: SPRINGER WIEN
: 2011
: Monatshefte für Mathematik
: MONATSHEFTE FUR MATHEMATIK
: MONATSH MATH
: 2
: 164
: 2
: 157
: 170
: 14
: 0026-9255
DOI: https://doi.org/10.1007/s00605-010-0236-6
Let l(n) be the number of lines through at least two points of an n x n rectangular grid. We prove recursive and asymptotic formulas for it using respectively combinatorial and number theoretic methods. We also study the ratio l(n)/l(n - 1). All this originates from Mustonen's experimental results.