Post by Thomas Plehn
can you show that the function defined by f(x,y)=1+a*x+b*y+c*xy is (nearly) a projectivity for large domain and small return values
for some abcdef,gh
the same as
(x,y)-->(f_x,f_y) is projectivity
or if not possible,
is it nearly the case for large domain and small return values?