1/3,2/8,3/15,4/24,5/35,6/48,.,根据规律可知第n个数应是?

1/3,2/8,3/15,4/24,5/35,6/48,.,根据规律可知第n个数应是?
1/3,2/8,3/15,4/24,5/35,6/48,.,根据规律可知第n个数应是?

1/3,2/8,3/15,4/24,5/35,6/48,.,根据规律可知第n个数应是?
数列的通项为 an = n/[n(n+2)] = 1/(n+2)
∴,第n个数为 n/[n(n+2)] ,约分后等于 1/(n+2)