  We interpret aspects of the Schur indices, that were identified with
characters of highest weight modules in Virasoro $(p,p')=(2,2k+3)$ minimal
models for $k=1,2,\dots$, in terms of paths that first appeared in exact
solutions in statistical mechanics. From that, we propose closed-form fermionic
sum expressions, that is, $q, t$-series with manifestly non-negative
coefficients, for two infinite-series of Macdonald indices of $(A_1,A_{2k})$
Argyres-Douglas theories that correspond to $t$-refinements of Virasoro
$(p,p')=(2,2k+3)$ minimal model characters, and two rank-2 Macdonald indices
that correspond to $t$-refinements of $\mathcal{W}_3$ non-unitary minimal model
characters. Our proposals match with computations from 4D $\mathcal{N} = 2$
gauge theories \textit{via} the TQFT picture, based on the work of J Song
arXiv:1509.06730.
