  In a previous paper, we introduced special types of fusions, so called
simple-ribbon fusions on links. A knot obtained from the trivial knot by a
finite sequence of simple-ribbon fusions is called a simple-ribbon knot. Every
ribbon knot with <10 crossings is a simple-ribbon knot. In this paper, we give
a formula for the Alexander polynomials of simple-ribbon knots. Using the
formula, we determine if a knot with 10 crossings is a simple-ribbon knot.
Every simple-ribbon fusion can be realized by ``elementary" simple-ribbon
fusions. We call a knot a p-simple-ribbon knot if the knot is obtained from the
trivial knot by a finite sequence of elementary p-simple-ribbon fusions for a
fixed positive integer p. We provide a condition for a simple-ribbon knot to be
both of an m-simple-ribbon knot and an n-simple-ribbon knot for positive
integers m and n.
