| ⊦ i > 0 ∧ # ints > 1 → addmultiarrays(refs, i, acc, ty, ints, st) = addmultiarrays (firstn(# refs - i→n(countrefs(ints .rest)), refs), i - 1, lastn(i→n(countrefs(ints .rest)), refs) .first + acc, ty, ints, addmultiarrays(lastn(i→n(countrefs(ints .rest)), refs), ints .rest .first, [], ty, ints .rest, st)) |