[" For a positive integer "n," let "],[a(n)=1+(1)/(2)+(1)/(3)+(1)/(4)+...(1)/((2^(n))-1)." Then "(1999-3" Marks) "]

Let S_(n)=1+(1)/(2)+(1)/(3)+(1)/(4)+......+(1)/(2^(n)-1) Then

For a positive integer (n gt 1) , Let a (n) = 1+ (1)/(2) + (1)/(3) + (1)/(4) ….... + (1)/( (2^(n) )-1) Then

For a positive integer n let a(n)=1+(1)/(2)+(1)/(3)+(1)/(4)cdots+(1)/((2^(n))-1). Then a(100) 100c.a(200)<=100d.a(200)<=100

For a positive integer n , let a(n) = 1+ 1/2 + 1/3 +…+ 1/(2^(n)-1) : Then

For a positive integer n let a(n)=1+1/2+1/3+1/4+.....+1/((2^n)-1)dot Then

If n is a positive integer, then (sqrt(3)+1)^(2n)-(sqrt(3)-1)^(2n) is

for a fixed positive integer n let then (D)/((n-1)!(n+1)!(n+3)!) is equal to