odditudes-and-weirdities

Happy Powerful Numbers Day! Powerful numbers  (aka squareful numbers) are ones such that for every number dividing it that is prime or 1, the square of the divisor is also a divisor. Powerful numbers are basically a subset of the composite numbers in addition to the number 1, and contain the square numbers as a subset. Here's some of the arithmetic that determines powerful numbers. We celebrate Powerful Numbers Day today because 9 and 27 are the largest powerful numbers that form a valid date: 9/27 or September 27.

Happy Square Numbers Day! Square numbers are the numbers formed when you square a positive integer, making them a fairly easy concept to grasp. Here is the beginning of the sequence: While triangular numbers are the integers representing the number of objects needed to form equilateral triangles, square numbers similarly form squares of different sizes. They are also a subset of the powerful numbers . We celebrate today as Square Numbers Day because the 2 largest consecutive square numbers that form a date are 9 and 16: 9/16 or September 16.