The indication of the illuminated sign mentioned in the question cannot be determined without further context or visual information.
Without the provided context or an image of the illuminated sign mentioned in the question, it is impossible to determine what numeral or symbol the sign is supposed to indicate. An illuminated sign could display any number or symbol, and without additional information, such as what kind of sign it is or the environment in which it is situated, we cannot infer the correct answer. Therefore, the appropriate response based on the information available is that the indication of the illuminated sign cannot be determined.
In mathematics, clarity of information is essential to find a solution. Without specific details or visual representation, we cannot accurately interpret or solve a problem. This serves as a fundamental lesson in problem-solving: ensure all the necessary data is available to reach a conclusion