## E3dtest.txt      check of P-Q pairs
#  if following X** =0, then the relation EPQE holds
with(DEtools):
read "equations.txt":
read "E3dPQ.txt":

e3dpq:=proc(A,B,EE) 
         return(factor(mult(EE,A,[dx,x])-mult(B,E3d,[dx,x]))):  end proc:

X1p:=e3dpq(P1p,Q1p,subs(e1=e1+1,E3d));
X1n:=e3dpq(P1n,Q1n,subs(e1=e1-1,E3d));
X3pp:=e3dpq(P3pp,Q3pp,subs(e3=e3+2,E3d));
X3nn:=e3dpq(P3nn,Q3nn,subs(e3=e3-2,E3d));
X4pp:=e3dpq(P4pp,Q4pp,subs(e4=e4+2,E3d));
X4nn:=e3dpq(P4nn,Q4nn,subs(e4=e4-2,E3d));
X6pp:=e3dpq(P6pp,Q6pp,subs(e6=e6+2,E3d));
X6np:=e3dpq(P6nn,Q6nn,subs(e6=e6-2,E3d));