THE SET OF SEMI-OCTAVE. I
In the present work based on a similar approach introduced by X. Mortazaasl and M. Jafari, we introduced the concept of semi-octave and operations on them, set properties of these operations. Obtained in this paper results will be further used in solving linear equations over semi-octave, as well as to establish the formulas of Euler and de Moivre to semi-octave.