In the sequence of fractions {1/1, 2/1, 1/2, 3/1, 2/2, 1/3, 4/1, 3/2, 2/3, 1/4, 5/1, 4/2, 3/3, 2/4, 1/5, 6/1, ...} fractions equivalent to any given fraction occur many times. For example, fractions equivalent to 1/2 occur for the first two times in positions 3 and 14.
In which position is the fifth occurrence of a fraction equivalent to 3/7?