C
chamhocgame


tính:
S=[TEX](2*n+1)C1[/TEX]-[TEX]2*2*(2*n+1)C2[/TEX]+......+(2*n+1)*2^2n*[TEX](2*n+1)C(2*n+1)[/TEX]
S=[TEX](2*n+1)C1[/TEX]-[TEX]2*2*(2*n+1)C2[/TEX]+......+(2*n+1)*2^2n*[TEX](2*n+1)C(2*n+1)[/TEX]