A circle `x^2+y^2+4x-2sqrt(2)y+c=0` is the director circle of the circle `S_1a n dS_1` is the director circle of circle `S_2,` and so on. If the sum of radii of all these circles is 2, then the value of `c` is `ksqrt(2)` , where the value of `k` is___________