English
The coset of transferFunction(H,g,q) is exactly q; i.e., transferFunction selects a representative of q whose image in G/H is q.
Русский
Косет transferFunction(H,g,q) в G/H равен q; то есть transferFunction выбирает представитель косета, образ которого в G/H равен q.
LaTeX
$$$\pi\bigl(\mathrm{transferFunction}(H,g,q)\bigr) = q$$$
Lean4
theorem coe_transferFunction (q : G ⧸ H) : ↑(transferFunction H g q) = q := by
rw [transferFunction_apply, ← smul_eq_mul, Quotient.coe_smul_out, ← quotientEquivSigmaZMod_symm_apply, Sigma.eta,
symm_apply_apply]