Maximum value of n for which `sum_(r=1)^(n+15)1>sum_(r=1)^n(r+1/2)` is

(sum_(r=1)^n r^4)/(sum_(r=1)^n r^2) is equal to

sum_(r=1)^n(2r+1)=...... .

The value of sum_(r=1)^(n)(-1)^(r-1)((r )/(r+1))*^(n)C_(r ) is

The value of lim_(n rarr oo)(1*sum_(r=1)^(n)(r)+2*sum_(r=1)^(n-1)(r)+3sum_(r=1)^(n-2)(r)+....+n.1)/(n^(4))

The value of sum_(r=1)^(n+1)(sum_(k=1)^(n)C(k,r-1))=

If sum_(r=1)^(n) r=210, then : sum_(r=1)^(n) r^(2) =

The valueof sum_(r=1)^(n)r^(4)-sum_(r=1)^(n+2)(n+1-r)^(4) is equal to

The value of sum_(r=1)^(n+1)(sum_(k=1)^n ^kC_(r-1)) (where r, k, n in N ) is equal to