odditudes-and-weirdities

Drug abuse resistance education, getting to know your customer, asking atheists about their beliefs, baseball pioneer Jackie Robinson, cakes that resemble pizzas, glazed spiral ham, and mathematical notation are subjects covered by today's observances: Ask an Atheist Day Get to Know Your Customer Day International Pizza Cake Day Jackie Robinson Day Mathematical Notation Day National D.A.R.E. Day National Glazed Spiral Ham Day D.A.R.E. is an acronym for drug abuse resistance education. After eating pizza, the most appropriate dessert is probably cake that looks like pizza. On this date in 1947 Major League Baseball's color barrier was shattered with Jackie Robinson played in his first game for the Brooklyn Dodgers. Image by  Welcome to all and thank you for your visit ! ツ  from  Pixabay

On this date in 1707 the Swiss mathematician Leonhard Euler was born. (Technically he was only born Swiss; the mathematician part came later. And he was also pretty adept at physics, astronomy, engineering, logic, and geography, probably more of a polymath.) Considered one of the greatest mathematicians in history, his contributions to the field live on in much of the mathematics we do today: Assigned the Greek letter π to the number representing the ratio of a circle's circumference to its diameter (3.14...), Created the number e to represent a logarithm's natural base (2.71...), Assigned the letter i to represent the square root of -1, Introduced the notation f(x) to describe the y-axis of a function, And used Σ to represent summation.