If you feel a little odd today, your calendar might explain why. Today’s date, 9/11/13, is a mathematical phenomenon so rare that it only occurs five times every 100 years. This is the last time for ...

(AP) — A retired teacher is calling on people to do some odd things today — 7/9/11 — one of only six dates this century that features three consecutive odd numbers. Ron Gordon has set up a web site to ...

Prepare to be awed by Odd Day. For the mathematically challenged, Thursday’s date, 5/7/09, is one of only six this century that will feature three consecutive odd numbers. Numbers lovers say the rare ...

All of these puzzles relate to adding together consecutive numbers. Mathematicians do not like doing a lot of, tedious adding up, and so are always on the lookout for cunning shortcuts. It might help ...

Today is the last time this century that the date will consist of consecutive odd numbers. The date reads 9/11/13 and the unusual sequence of numbers will not be repeated until March 1, 2105 (1/3/5).