How about this one to get you started -
13 (along with 5 and 563) is one of only three known Wilson primes. Named after English mathematician John Wilson, this is a prime number p such that p2 divides (p − 1)! + 1, where "!" denotes the factorial function (ie. 13x12x11x10 ...x1).
i.e. (13-1)! + 1 / (13x13) is an integer
12! + 1 / 169 = 479001601 / 169 = 2834329
Try to come up with a list of interesting facts without using Wikipedia!
Sometimes Mr Marlow your fascination with numbers and what you find interesting amazes even me. What is even more disturbing is that referring to yourself in the 3rd person is a definite sign of madness!!
ReplyDeleteHere are my answers (and no I didn't look at Wikipedia!)
ReplyDelete13 is a prime number
13 is an odd number
13 is when you become a teenager
In most places 13 is considered unlucky, although the Italians would disagree
13 squared is a 169
Square root of 13 is irrational
13 cards in a suit
5, 12, 13 is a Pythagorean triple
13 players on a rugby league team
13 is a Fibonacci number (1, 1, 2, 3, 5, 8, 13 ...)