- Nooksack River § South Fork (Wikipedia)
The South Fork Nooksack River, about 50 miles (80 km) long, rises in southern Whatcom County, east of Twin Sisters Mountain near Bell Pass and Lake Wiseman. It flows briefly south, entering Skagit County, then northwest to re-enter Whatcom County. It flows past the town of Acme, and due north until merging with the North Fork near the State Route 9 bridge, 1.6 km (1 mi) southeast of Deming and the Nooksack Indian Reservation.
- Sierpiński triangle (Wikipedia)
The Sierpiński triangle, also called the Sierpiński gasket or Sierpiński sieve, is a fractal with the overall shape of an equilateral triangle, subdivided recursively into smaller equilateral triangles. Originally constructed as a curve, this is one of the basic examples of self-similar sets—that is, it is a mathematically generated pattern that is reproducible at any magnification or reduction. It is named after the Polish mathematician Wacław Sierpiński, but appeared as a decorative pattern many centuries before the work of Sierpiński.
