A=matrix([[101,201,301],[102,202,302],[103,203,303]])
a=A.echelon_form()
print a[0,0]*a[1,1]*a[2,2]
t=var('t')
B=matrix([[1,t,t*t],[t,1,t],[t*t,t,1]])
b=B.echelon_form()
print b[0,0]*b[1,1]*b[2,2]