optimize code regarding for loop

Hallo :

    if k <= 0
          int = x ;
          return
      end
      int = zeros(1,length(x));
      c=(k-1)/factorial(k-1);
      dth2=dt/2;
      lenx=length(x);
      ft1=((lenx:-1:0)*dt).^(c);
      for n = 3:lenx
          y1 = x(2:n) ;
          t1 = ft1(lenx-n+3:lenx+1) ;
          y2 = x(1:n-1) ;
         t2 = t1 +dt; 
          int(n) = sum (t1.*y1 + (t2.^c).*y2)*dth2 ;

    end

How can I compute .^c for the line contains t2.^c , out and before the for loop?

Why would you want to? what is the goal of doing this?