Sqi: H ()+(K)--defined for any complex K, satisfying, among several others, the following
properties: for any map f of one complex into another, f* Sq'= Sq'f*; Sqo= identity; Sq" u= uu,(mod …

1. For any complex K and odd prime p, the cyclic reduced power operations are homomorphism
(8,(s= 0, 1,...), 9P: H"(K; Zp,)--. Hg+ 28 (P-1)(K; Z) They satisfy the following properties: …

THE purpose of the present paper is to give complete proof of some of the results previously
announced by the author (cf.[1, 2]). The main result states tjiat the iterated Steenrod^-. …

The Stiefel-Whitney classes of a real vector bundle are determined by the Thom isomorphism
and the action of the Steenrod squares on the fundamental class of the bundle. With an …

This paper contains generalizations of some results presented in part I. Here, for an arbitrary
field F of characteristic not two, the non-existence of normed maps F4h+ ix F3-F4h+ 2 and F …

Let f be the Hopf bundle over the n-dimensional real projective space RPn. As is known ([12]),
RP" immerses in the euclidean space Rn+ k if and only if the bundle (n+ k+ l) f has n+ 1 …

As it is well known, the real projective space pn has an immersion in the euclidean k-space
R\if and only if there exists a nonsingular skew-linear map f: Rn+ i X Rn+ i-Rk+ 1, with k> n. …

Sk over the real projective space pk. As it is known ([2J,[4J), the bundle has s independent
sections if and only if there maps give raise to several nonsingu1ar bilinear maps exists a …

A/= Yil,(j, k= 1,••·, r; j"'F k), where J is the identity matrix and each Yi= 1 or-1. Matrices
fulfilling condition (1.2) are said to anticommute. Let!! it and f denote the number of matrices, …

José Adem nació en Tuxpan, Veracruz, el 27 de octubre de 1921. En 1941 partió a la Ciudad
de México para ingresar a la Escuela Nacional de Ingenieros de la unam. En 1949 se …