>Can any one tell me the word used to describe the occurance of a series of the same number in a date such as
9/9/99?

In the absolutely fascinating book, "The Man Who Loved Only Numbers", by Paul Hoffman, there is a reference on page 206 to a mathematical concept called the repunit, short for repeating unit. I know this is probably not the word for which you are looking, but it does appear to be a technically correct answer to your question.

The book, by the way, is about an extrememly eccentric mathematician named Paul Erdos. The o in his name has a mark over it that looks like a double quote mark. I had been only vaguely aware of Erdos, and after reading the book I came away with that feeling you get when you run across true genius.


TEd