Dividing a circle into areas lines (there are two points on one side and one on the other). So the recurrence can be expressed as which can be easily reduced to using the sums of the first formula_3 natural numbers and the first formula_3 squares, this combines to Finally which yields The lemma asserts that the number of regions is maximal if all "inner" intersections of chords are simple (exactly two chords pass through each point of intersection in the interior). This will be the case if the points on the circle are chosen "in general position". Under this assumption of "generic intersection", the number
Circle MRT line road was temporarily closed to traffic. On 20 September 2011, a power fault disrupted train services on all 16 stations on the Circle line. The four hours delay left thousands of commuters stranded during rush-hour. It was reported that leaks and a damaged electrical cable along the Circle line were the cause of the disruption. The disruption started at about 5.30 am. Train services were gradually restored from 8am and all services were restored just before 10am. Dakota and Mountbatten stations were the last two to resume operations. Investigations were carried out. It was later found that a faulty cable