The polymatroid Tutte polynomial is an activity generating polynomial for the integer bases of an integral polymatroid.
Fix a total order on its ground set , let
be its set of integer bases, and let
denote the coordinate unit vector
at
.
For a basis
,
an element
is internally active if
for every
, and externally active if
for every
. Writing
,
, and
for the numbers of only internally active, only externally
active, and simultaneously active elements gives
The polynomial is independent of the chosen total order (Tóthmérész 2026).
For a matroid of rank on
elements, this normalization is related to its ordinary Tutte polynomial
by
The right side is interpreted as the polynomial obtained after cancellation, including when or
is zero. For example, one element with one integer basis gives
.
Tóthmérész (2026) proves that computation-tree activities, using either a minimum or a maximum rule, also yield this polynomial. The hypergraph Tutte polynomial is a special case using the integer bases supplied by a connected hypergraph.