Today's date, 7/11/13 is interesting, as it consists solely of consecutive prime numbers. The only other times this century that this will happens are on 2/3/05, 3/5/07, 5/7/11, and 11/13/17.

Since the date brings us a prime pattern, today seems like a good day to look at prime patterns.

With help from Brady at numberphile, James Grime starts us off by explaining the concept of prime spirals:



Numberphile didn't stop there, though. Starting from a passage in one of Arthur C. Clarke's book, the following video discusses the importance of the number 41 to Ulam's spiral:



While they don't show every step in the video, Wolfram|Alpha can show you all the results of n²-n+41 quickly and easily.

I hope pondering these interesting patterns gives you plenty of food for thought!