1/2,1/6,1/12,1/30,1/42…… Find the rule, the nth number is () 1 / 132 is the number

1/2,1/6,1/12,1/30,1/42…… Find the rule, the nth number is () 1 / 132 is the number

1/n*(n+1)
1 / 132 = 1 / 12 * (12 + 1), the twelfth