forA21 = -((n*Csc[eps - i]*(C11*((a*e)/(2*R) - (3*a*e^3)/(8*R))*Sin[eps] + C20*(-3/8 - (9*e^2)/16 - (45*e^4)/64)*Sin[2*eps] + C22*(((51*e^2)/8 - (115*e^4)/8)*Sin[eps] + ((51*e^2)/16 - (115*e^4)/16)*Sin[2*eps]) + (C33*R*((36675*e^3*Sin[eps])/256 + (7335*e^3*Sin[2*eps])/64 + (7335*e^3*Sin[3*eps])/256))/a + (C31*R*(((-9*e)/128 - (33*e^3)/512)*Sin[eps] + ((-45*e)/32 - (165*e^3)/128)*Sin[2*eps] + ((-405*e)/128 - (1485*e^3)/512)*Sin[3*eps]))/a + (C44*R^2*((1211035*e^4*Sin[eps])/256 + (1211035*e^4*Sin[2*eps])/256 + (519015*e^4*Sin[3*eps])/256 + (173005*e^4*Sin[4*eps])/512))/a^2 + (C40*R^2*((15/128 + (75*e^2)/128 + (1575*e^4)/1024)*Sin[2*eps] + (105/256 + (525*e^2)/256 + (11025*e^4)/2048)*Sin[4*eps]))/a^2 + (C42*R^2*(((-795*e^2)/256 + (895*e^4)/512)*Sin[eps] + ((-795*e^2)/64 + (895*e^4)/128)*Sin[2*eps] + ((-16695*e^2)/256 + (18795*e^4)/512)*Sin[3*eps] + ((-5565*e^2)/128 + (6265*e^4)/256)*Sin[4*eps]))/a^2))/(Omd*(1 + omd/(2*n) + (Omd*Cos[eps - i])/(2*n))))