loreq17(t,u)

function udot = loreq17(t,u)
global U V t0 k1 k2 k3 k4 k21 k22 k23 k24 a m1 m2 m3 m4 mu d0 d2
udot =[i.*((t0 +  a * (u(19)- u(17)))*u(3)  -( t0 + a * (u(19)- u(17)))*u(2)).*exp(i.*V);
       i.*((t0 +  a * (u(19)- u(17)))*u(4)  -( t0 + a * (u(20)- u(18)))*u(1)  +(U./2.*(u(5)-u(8))).*u(2)).*exp(i.*V);
       i.*((t0 +  a * (u(20)- u(18)))*u(1)  -( t0 + a * (u(19)- u(17)))*u(4)  +(U./2.*(u(8)-u(5))).*u(3)).*exp(i.*V);
       i.*((t0 +  a * (u(20)- u(18)))*u(2)  -( t0 + a * (u(20)- u(18)))*u(3)).*exp(i.*V);
       i.*((t0 +  a * (u(19)- u(17)))*u(7)  -( t0 + a * (u(18)- u(17)))*u(6)).*exp(i.*V);
       i.*((t0 +  a * (u(19)- u(17)))*u(8)  -( t0 + a * (u(20)- u(18)))*u(5)  +(U./2.*(u(1)-u(4))).*u(6)).*exp(i.*V);
       i.*((t0 +  a * (u(20)- u(18)))*u(5)  -( t0 + a * (u(19)- u(17)))*u(8)  +(U./2.*(u(4)-u(1))).*u(7)).*exp(i.*V);
       i.*((t0 +  a * (u(20)- u(18)))*u(6)  -( t0 + a * (u(20)- u(18)))*u(7)).*exp(i.*V);
       i.*((t0 +  a * (u(19)- u(17)))*u(11) -( t0 + a * (u(19)- u(17)))*u(10) +(U./2.*(u(5)-u(1))).*u(9)).*exp(i.*V);
       i.*((t0 +  a * (u(19)- u(17)))*u(12) -( t0 + a * (u(20)- u(18)))*u(9)  +(U./2.*(u(5)-u(4))).*u(10)).*exp(i.*V);
       i.*((t0 +  a * (u(20)- u(18)))*u(9)  -( t0 + a * (u(19)- u(17)))*u(12) +(U./2.*(u(8)-u(1))).*u(11)).*exp(i.*V);
       i.*((t0 +  a * (u(20)- u(18)))*u(10) -( t0 + a * (u(20)- u(18)))*u(11) +(U./2.*(u(8)-u(4))).*u(12)).*exp(i.*V);
       i.*((t0 +  a * (u(19)- u(17)))*u(15) -( t0 + a * (u(19)- u(17)))*u(14) +(U./2.*(u(1)-u(8))).*u(13)).*exp(i.*V);
       i.*((t0 +  a * (u(19)- u(17)))*u(16) -( t0 + a * (u(20)- u(18)))*u(13) +(U./2.*(u(1)-u(8))).*u(14)).*exp(i.*V);
       i.*((t0 +  a * (u(20)- u(18)))*u(13) -( t0 + a * (u(19)- u(17)))*u(16) +(U./2.*(u(4)-u(5))).*u(15)).*exp(i.*V);
       i.*((t0 +  a * (u(20)- u(18)))*u(14) -( t0 + a * (u(20)- u(18)))*u(15) +(U./2.*(u(4)-u(8))).*u(16)).*exp(i.*V);
-m1*u(21)  ;
-m2*u(22)  ;
-m3*u(23)  ;
-m3*u(24)  ;
 ( k1*u(17) +  k21 *u(17)*u(17)*u(17)- a * ( u(2)-u(3)+u(6)-u(7)+u(10)-u(11)+u(14)-u(15)));
 ( k2*u(18) +  k22 *u(18)*u(18)*u(18)- a * (-u(2)+u(3)-u(6)+u(7)-u(10)+u(11)-u(14)+u(15)));
 ( k3*u(19) +  k23 *u(19)*u(19)*u(19)- a * (-u(2)+u(3)-u(6)+u(7)+u(10)-u(11)+u(14)-u(15)));
 ( k3*u(20) +  k24 *u(20)*u(20)*u(20)- a * ( u(2)-u(3)+u(6)-u(7)-u(10)+u(11)-u(14)+u(15)));
];