= Indecomposable count for a cyclic defect block
{title2=$l(B)=e,\quad\#\operatorname{ind}(B)=ep^n$}
For a split <block of a group algebra> with cyclic <defect group of a block> of order $q=p^n$ and <inertial index of a block> $e$, its <Brauer tree algebra> has $e$ simple modules and exceptional multiplicity $(q-1)/e$. Its <stable Auslander–Reiten quiver> is $\mathbb ZA_{q-1}/\langle\tau^e\rangle$, giving $e(q-1)$ nonprojective indecomposables. Adding the $e$ indecomposable projectives gives $eq$ indecomposables in total.
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