an=√Sn+√S(n-1)
sn-s(n-1)=√Sn+√S(n-1)
[√Sn+√S(n-1)][√Sn-√S(n-1)]=[√Sn+√S(n-1)]
[√Sn-√S(n-1)]=1
{√Sn}等差数列,公差为:1;首项为:1
√Sn=n
sn=n^2
an=n^2-(n-1)^2=2n-1
an=√Sn+√S(n-1)
sn-s(n-1)=√Sn+√S(n-1)
[√Sn+√S(n-1)][√Sn-√S(n-1)]=[√Sn+√S(n-1)]
[√Sn-√S(n-1)]=1
{√Sn}等差数列,公差为:1;首项为:1
√Sn=n
sn=n^2
an=n^2-(n-1)^2=2n-1