Octadecagon Octadecagon An octadecagon (or octakaidecagon) or 18-gon is an eighteen-sided polygon. A "regular octadecagon" has a Schläfli symbol {18} and can be constructed as a quasiregular truncated enneagon, t{9}, which alternates two types of edges. As 18 = 2 × 3, a regular octadecagon cannot be constructed using a compass and straightedge. However, it is constructible using neusis, or an angle trisection with a tomahawk. The following approximate construction is very similar to that of the enneagon, as an octadecagon can be constructed as a truncated enneagon. It is also feasible with exclusive use of compass and straightedge. The "regular
How Long, How Long Blues How Long, How Long Blues "How Long, How Long Blues" (also known as "How Long Blues" or "How Long How Long") is a blues song recorded by the American blues duo Leroy Carr and Scrapper Blackwell in 1928. The song became "an instant best-seller" and one of the first blues standards, inspiring many blues songs of the era. It has been recorded by many artists, not only in blues but also country and western, pop, and jazz. "How Long, How Long Blues" is based on "How Long Daddy", recorded in 1925 by Ida Cox with Papa Charlie Jackson. Leroy Carr