Subject: char classes
From: wolfgang Ziller <wziller@math.upenn.edu>
Date: Tue, 20 Dec 2005 23:39:26 -0200

I would like to know what kind of information is
contained in the Pontryagin classes that are homotopy invariants.
I know a theorem by Hirzebruch that p_1(M) mod 24
is a homotopy invariant.
What other combinations like this, mod some integer,
are homotopy invariants.
Any that involve only p_1 and p_2 ?
Any references would be welcome.

wolfgang ziller