apply List.foldl_hom
α : Type u
inst✝¹ : LinearLT α
inst✝ : DecidableRel LT.lt
deg : α → Nat
a : α
n : valType
xs : KVChain LT.lt fun x => valType
haxs : KVChain.boundLeft a xs
⊢ List.foldl (fun c x => c + deg x.fst * x.snd.val) (deg a * n.val + 0) xs.toList =
    deg a * n.val + List.foldl (fun c x => c + deg x.fst * x.snd.val) 0 xs.toList
case H
α : Type u
inst✝¹ : LinearLT α
inst✝ : DecidableRel LT.lt
deg : α → Nat
a : α
n : valType
xs : KVChain LT.lt fun x => valType
haxs : KVChain.boundLeft a xs
⊢ ∀ (x : Nat) (y : (_ : α) × valType),
    deg a * n.val + x + deg y.fst * y.snd.val = deg a * n.val + (x + deg y.fst * y.snd.val)