Proof of Fermat Last Theorem based on successive presentations of pairs of odd numbers

A simpler proof of Fermat Last Theorem (FLT), formulated by Fermat in 1637, is suggested. The initial equation x^n + y^n = z^n is considered not in natural, but in integer numbers. It is subdivided into four equations based on parity of terms and their powers. Cases 1, 3 and 4 converge to case 2, which is studied using presentation of pairs of odd numbers with a successively increasing presentation factor of 2^r. The proposed methods and ideas can be used for studying other problems in number theory.