The ornamental design for a sectionalsofa, as shown and described.
FIG. 1 is a perspective view of the sectional sofa according to my new
design, looking from the front and top, it being understood that the back
and bottom are plain and unadorned; and
FIG. 2 is an exploded perspective view of the sectional sofa according to
FIG. 1, looking from the front and top and illustrating the sides of each
of the sections.