Today's number is 13
13 is
13 is a prime number, it is the 6th prime
13 is also a prime if the digits are reversed (31)
13 is a pythagorean prime (13 = 3**2 + 4**2 & 13 = 4n+1 where n =3)
March 13 is the 72nd day of the year. There are 293 days left.
Today's number is 13
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13 is
13 is a prime number, it is the 6th prime
13 is a Wilson Prime (see numberphile video)
13 is also a prime if the digits are reversed (31).
February 13, 2017 Open Thread; happy World Radio Day
February 13 is the 44th day of the year. There are 321 days left.
Today's number is 13
13 is
13 is a prime number, it is the 6th prime
13 is also a prime if the digits are reversed (31).
June 13 is the 164th day of the year, there are 201 days left in 2016
13 is a prime number, it is the 6th prime
13 is also a prime if the digits are reversed (31).
13 is a fibonacci number (0,1,1,2,3,5,8,13).
13 is the hypotenuse of a right traingle with sides of 5 & 12. 5, 12 & 13 can be used to test for right angles, like 3,4 & 5 can
