%I #8 Dec 30 2012 01:50:18
%S 32,46,50,52,78,86,94,102,106,158,166,174,182
%N Davis's upper bound for span(P^m x P^111) with m = 3 * (2^n  1) for 5 <= n <= 17, and P^k denoting real projective space.
%C From Table 3.2, p.10, of Davis. The span of a manifold is its maximum number of linearly independent vector fields. We discuss the question, still unresolved, of whether span(P^m x P^n) always equals span(P^m) + span(P^n). Here P^n denotes real projective space. We use BPcohomology to obtain new upper bounds for span(P^m x P^n), much stronger than previously known bounds.
%H Donald M. Davis, <a href="http://arxiv.org/abs/1012.3952">Vector fields on RP^m x RP^n</a>, Dec 17, 2010.
%K nonn
%O 5,1
%A _Jonathan Vos Post_, Dec 20 2010
