a1 Département de Mathématique, Université Louis Pasteur, 67084 Strasbourg Cedex, France
a2 Econometric Institute, Erasmus University Rotterdam, P.O. Box 1738, 3000 Rotterdam, The Netherlands
J. H. E. Cohn solved the diophantine equations x2 + 74 = yn and x2 + 86 = yn, with the condition 5 n, by more or less elementary methods. We complete this work by solving these equations for 5 | n, by less elementary methods.
(Received August 15 1994)