Length-preserving monomorphisms for Steenrod algebras at odd primes

Abstract

Let p be an odd prime. In this paper we determine the group of length-preserving automorphisms for the ordinary Steenrod algebra A(p) and for $${\mathcal {B}}(p)$$ , the algebra of cohomology operations for the cohomology of cocommutative $$\mathbb {F}_p$$ -Hopf algebras. Contrarily to the $$p=2$$ case, no length-preserving strict monomorphism turns out to exist.