The ornamental design for a stand for a flatpanel television, as shown and described.
FIG. 1 is a front perspective view of a stand for a flat panel television;
FIG. 2 is a rear perspective view thereof;
FIG. 3 is another front view thereof;
FIG. 4 is an another rear view thereof;
FIG. 5 is a first end view thereof; and,
FIG. 6 is a second end view thereof.
The broken lines showing the flat panel television and a portion inside the stand are included for the purpose of illustrating environment and form no part of the claimed design.