1 / 2, 1 / 2, 5 / 12, 7 / 20, fill in the numbers according to the rules, followed by the numbers

1 / 2, 1 / 2, 5 / 12, 7 / 20, fill in the numbers according to the rules, followed by the numbers

Just think of the second as three sixths
Denominator: 1 * 2,2 * 3,3 * 4,4 * 5
Molecules: 1,3,5,7,9
The answer is nine out of thirty

Find the rules: 1 / 3, 1 / 2, 5 / 9, 7 / 12, 3 / 5, 11 / 18, (), ()

13/21,5/8

It's a process to find rules and fill in half, 1,1, (), nine out of eleven, eleven out of thirteen

The denominator is a continuous prime number. Is it so difficult? Then the numerator is a continuous odd number
1/2,3/3,5/5,7/7,9/11,11/13

Find the rules. [one third] [one half] [five ninth] [seven twelfth] [three fifths] [eleven eighteenth]
And get the 100th number

The original sequence can be changed into: 1 / 3, 3 / 6, 5 / 9, 7 / 12, 9 / 15, 11 / 18;
It can be seen that the molecule is 2N-1 and the denominator is 3N,
So the 100th number is 199 / 300