odditudes-and-weirdities

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.

It's Triangular Numbers Day, the day we all joyously celebrate the triangular numbers ! The triangular numbers are the number of figures needed to create an equilateral triangle. They are also the numbers representing the sum of each of the natural numbers : 0 0+1 = 1 0+1+2 = 3 0+1+2+3 = 6 0+1+2+3+4 = 10 etc. This summation is probably the most useful characteristic of triangular numbers; after that they're probably more of a curiosity. A list of the start of the series can be found here . October 15 was chosen as Triangular Numbers Day because 10/15 is the latest date that can be formed using consecutive triangular numbers.