Formula One World Drivers' Championship was not formalised until 1947. The first world championship race was held at Silverstone, United Kingdom in 1950. A championship for constructors followed in 1958. National championships existed in South Africa and the UK in the 1960s and 1970s. Non-championship Formula One events were held for many years, but due to the increasing cost of competition, the last of these occurred in 1983. On 26 November 2017, Formula One unveiled its new logo, following the 2017 season finale in Abu Dhabi during the Abu Dhabi Grand Prix at Yas Marina Circuit. The new logo replaced F1's iconic
Circuit rank of any planar graph with the same vertex set, is called the meshedness coefficient. For a connected planar graph with edges and vertices, the meshedness coefficient can be computed by the formula Here, the numerator formula_5 of the formula is the circuit rank of the given graph, and the denominator formula_6 is the largest possible circuit rank of an -vertex planar graph. The meshedness coefficient ranges between 0 for trees and 1 for maximal planar graphs. The circuit rank controls the number of ears in an ear decomposition of a graph, a partition of the edges of the graph into