1 ((5*k^6 + 2*k^4*(15 - 8*Sqrt[1 + k^2/(c - I*k0)^2])*(c - I*k0)^2 + 8*k^2*(5 - 4*Sqrt[1 + k^2/(c - I*k0)^2])*(c - I*k0)^4 - 16*(-1 + Sqrt[1 + k^2/(c - I*k0)^2])*(c - I*k0)^6)/(240*k^4) - (7*(5*k^6 + 2*k^4*(15 - 8*Sqrt[1 + k^2/(2*c - I*k0)^2])*(2*c - I*k0)^2 + 8*k^2*(5 - 4*Sqrt[1 + k^2/(2*c - I*k0)^2])*(2*c - I*k0)^4 - 16*(-1 + Sqrt[1 + k^2/(2*c - I*k0)^2])*(2*c - I*k0)^6))/(240*k^4) + (7*(5*k^6 + 2*k^4*(15 - 8*Sqrt[1 + k^2/(3*c - I*k0)^2])*(3*c - I*k0)^2 + 8*k^2*(5 - 4*Sqrt[1 + k^2/(3*c - I*k0)^2])*(3*c - I*k0)^4 - 16*(-1 + Sqrt[1 + k^2/(3*c - I*k0)^2])*(3*c - I*k0)^6))/(80*k^4) - (7*(5*k^6 + 2*k^4*(15 - 8*Sqrt[1 + k^2/(4*c - I*k0)^2])*(4*c - I*k0)^2 + 8*k^2*(5 - 4*Sqrt[1 + k^2/(4*c - I*k0)^2])*(4*c - I*k0)^4 - 16*(-1 + Sqrt[1 + k^2/(4*c - I*k0)^2])*(4*c - I*k0)^6))/(48*k^4) + (7*(5*k^6 + 2*k^4*(15 - 8*Sqrt[1 + k^2/(5*c - I*k0)^2])*(5*c - I*k0)^2 + 8*k^2*(5 - 4*Sqrt[1 + k^2/(5*c - I*k0)^2])*(5*c - I*k0)^4 - 16*(-1 + Sqrt[1 + k^2/(5*c - I*k0)^2])*(5*c - I*k0)^6))/(48*k^4) - (7*(5*k^6 + 2*k^4*(15 - 8*Sqrt[1 + k^2/(6*c - I*k0)^2])*(6*c - I*k0)^2 + 8*k^2*(5 - 4*Sqrt[1 + k^2/(6*c - I*k0)^2])*(6*c - I*k0)^4 - 16*(-1 + Sqrt[1 + k^2/(6*c - I*k0)^2])*(6*c - I*k0)^6))/(80*k^4) + (7*(5*k^6 + 2*k^4*(15 - 8*Sqrt[1 + k^2/(7*c - I*k0)^2])*(7*c - I*k0)^2 + 8*k^2*(5 - 4*Sqrt[1 + k^2/(7*c - I*k0)^2])*(7*c - I*k0)^4 - 16*(-1 + Sqrt[1 + k^2/(7*c - I*k0)^2])*(7*c - I*k0)^6))/(240*k^4) - (5*k^6 + 2*k^4*(15 - 8*Sqrt[1 + k^2/(8*c - I*k0)^2])*(8*c - I*k0)^2 + 8*k^2*(5 - 4*Sqrt[1 + k^2/(8*c - I*k0)^2])*(8*c - I*k0)^4 - 16*(-1 + Sqrt[1 + k^2/(8*c - I*k0)^2])*(8*c - I*k0)^6)/(240*k^4))/k0^4
2 SeriesData[k, Infinity, {(105*c^7)/k0^4, 0, (-315*(125*c^9 - (54*I)*c^8*k0 - 6*c^7*k0^2))/(4*k0^4), 0, (2079*(4819*c^11 - (3960*I)*c^10*k0 - 1250*c^9*k0^2 + (180*I)*c^8*k0^3 + 10*c^7*k0^4))/(16*k0^4)}, 5, 11, 1]