Identities in finite algebras
Roger C. Lyndon · Proceedings of the American Mathematical Society · 1954
By Bm and Cm for m <n, we can eliminate any repetition among the first n+1 arguments of Oa or of Og, whence we may suppose that A, v_?n and that neither product contains repetitions. If ka, say, is not 0, then setting Xal =c, Xa2 =. =Xa A=e, and any other x=O, gives 45a =c; it follows that 4, is not 0, and indeed that Xl1 = Xal, and that all the indeterminates of 4, are among those of 45a. By sym-