The congruence $f(x) + g(y) + c = 0$ $(mod$ $xy)$
Appears in collection : Diophantine approximation and transcendence / Approximation diophantienne et transcendance
The assertions made by L. J. Mordell in his paper in Acta Mathematica 44(1952) are discussed. Mordell had been to a certain extent anticipated by E. Jacobsthal (1939). backward induction - congruence - equation - non-zero coefficients - polynomials
