In this paper the author works only through the factorizzation in factors, with the proceeding for absurd, that is if x, y, z are prime among them, under the hypothesis that the tern of integers (x, y, z) were a solution of the equation xn + yn = zn. Then he obtains that the first and the second term of an equivalent relation are odd (the first) and even (the second). Three cases are separated: 1) n is power of 2; 2) n is odd; 3) n is product of a power of 2 for an odd number. For a better understanding also the Pythagorean set of three numbers is reported.
The Bulletin of Society for Mathematical Services and Standards (Volume 4)
N. Fragnito "The Last Theorem of Pierre de Fermat, In Elementary Way", The Bulletin of Society for Mathematical Services and Standards, Vol. 4, pp. 22-40, 2012