Go-go dancing 1960s-era clubgoers wore miniskirts and knee-high, high-heeled boots, which eventually came to be called go-go boots. Night club promoters in the mid‑1960s then conceived the idea of hiring women dressed in these outfits to entertain patrons. The term "go-go" derives from the phrase "go-go-go" for a high-energy person, and was influenced by the French expression "à gogo", meaning "in abundance, galore", which is in turn derived from the ancient French word "la gogue" for "joy, happiness". On 19 June 1964, Carol Doda began go-go dancing topless at the Condor Club on Broadway and Columbus in the North Beach neighborhood of
Combinatorics on words of the Post correspondence problem, which asks whether there exists a word formula_2 in the domain such that formula_3. Post proved that this problem is undecidable; consequently, any word problem that can be reduced to this basic problem is likewise undecidable. Combinatorics on words have applications on equations. Makanin proved that it is possible to find a solution for a finite system of equations, when the equations are constructed from words. Combinatorics on words Combinatorics on words is a fairly new field of mathematics, branching from combinatorics, which focuses on the study of words and formal languages. The subject looks