Cn=(n+1)/2^(n+1)
Tn=2/2²+3/2³+······+(n+1)/2^(n+1)①
2Tn=2/2+3/2²+4/2³+······+(n+1)/2^n②
Tn=2/2+1/2²+1/2³+······+1/2^n
-(n+1)/2^(n+1)
=1/2+(1-1/2^n)-(n+1)/2^(n+1)
=3/2-(n+3)/2^(n+1)
Cn=(n+1)/2^(n+1)
Tn=2/2²+3/2³+······+(n+1)/2^(n+1)①
2Tn=2/2+3/2²+4/2³+······+(n+1)/2^n②
Tn=2/2+1/2²+1/2³+······+1/2^n
-(n+1)/2^(n+1)
=1/2+(1-1/2^n)-(n+1)/2^(n+1)
=3/2-(n+3)/2^(n+1)