"Source: Text/Commut/RngDiff.text";
"Line: 943";
"Date: Thu Sep 25 14:47:46 2025";
"Main: Fri Sep 26 14:29:19 2025";
// original file: Text/Commut/RngDiff.text, line: 943
// Example: H121E14 ()
print "Example: H121E14";
ei := GetEchoInput();
SetEchoInput(true);
F<z> := RationalDifferentialField(Rationals());
_<X> := PolynomialRing(F);
K<x>, mp := ext<F|X^2+X+1>;
seq := Eltseq(x^2); 
seq;
Universe(seq) eq F;
assert $1;
SetEchoInput(ei);
