Visser Shift

GeoGebra imitating Kees Visser. Leslie Roberts reblogged Shift by Kees Visser this morning. More Kees Visser: Inspired a bit of GeoGebra tinkering. May be more to come. It’s actually two patterns, one of triangles and one of right trapezoids. Very interesting fractions questions. For an NxN square, which fractions are shown? Which fractions repeat? Can you come up with a formula for the fraction at spot (i,j)?