The ornamental design for an illuminateddisplaysign, as shown and described.
FIG. 1 is a perspective view of an embodiment of the illuminated display
sign of my design with the broken line showing for illustrative purposes
only and forming no part of the claimed design;
FIG. 2 is a front elevation of the embodiment of FIG. 1;
FIG. 3 is a left side elevation of the embodiment of FIG. 1; and,