数列{an}的前n项和Sn满足log2(Sn+1)=n+1则an=

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数列{an}的前n项和Sn满足log2(Sn+1)=n+1则an=

数列{an}的前n项和Sn满足log2(Sn+1)=n+1则an=
数列{an}的前n项和Sn满足log2(Sn+1)=n+1则an=

数列{an}的前n项和Sn满足log2(Sn+1)=n+1则an=
log2(Sn+1)=n+1
所以 Sn + 1 = 2^(n+1),Sn = 2^(n+1) -1,
a1 = S1 = 3
S(n-1) = 2^n -1,
an = Sn - S(n-1) = 2^(n+1) - 2^n = 2^n (n>=2)
所以
an = 3 (n=1)
2^n (n>=2)