  The explicit formula, which expresses the Alexander polynomials
\Delta_{n,3}(t) of torus knots T(n,3) as a sum of the Alexander polynomials
\Delta_{k,2}(t) of torus knots T(k,2), is found. Using this result and those
from our previous papers, we express the Alexander polynomials \Delta_{n,3}(t)
through Chebyshev polynomials. The latter result is extended to general torus
knots T(n,l) with n and l coprime.
