The Brown-Peterson spectrum at a prime
is the
-typical summand of
-local complex cobordism. In its usual coefficient
convention,
where .
The truncated spectrum
has coefficient ring
. Morava
K-theory isolates a chromatic height, whereas Smith-Toda
complexes realize finite quotients killing
and an initial string of these generators. A specification
of
homology as a comodule includes its coaction as well as
its underlying graded module.