Tag » Eratosthenes

Damascus Road: Midday

Indeed, my friends, let us not forget in our wakefulness…
(Saint Ephraim the Syrian, Hymns of the Nativity)

Do I assume this peace?
Some peasants once, I am told, 118 kata lagi


How To Disprove The Flat Earth

By @ScienceWasWrong

While retweeting flat earthers, as a Take That account, I was much struck with certain facts about the positions of the heavenly bodies, and in their relation to the geographic coordinates of the observer. 1.455 kata lagi


Is the Earth Actually Curved?

Back in the early stages of a ‘logic deduced world’ , a  Greek philosopher, Aristotle (384-322 BC) argued in his writings that the Earth was spherical, because of the circular shadow it cast on the Moon, during a lunar eclipse. 1.120 kata lagi


Primes below N, the sieve of Eratosthenes in Scala

I have been practicing coding tests again. One nice exercise I saw the other day was a sample from a HackerRank test: find the number of prime numbers less than N. 2.345 kata lagi

Number Theory

The Shadows of Alexandria

On this, the summer solstice, I have to post an animation I made a long time ago: The Shadows of Alexandria

In the third century BC, Eratosthenes was able to use the shadows cast during the summer solstice along with some simple measurements to accurately calculate the size of the Earth. 375 kata lagi

The Girth of the Earth: How do we know?

Recently I wrote about the circumference of the Earth, and how long it would take you to travel right round it. But how do we even know that? 774 kata lagi

How Big Is It?

A play on primes - Part 2

In a previous post, I shared some thoughts on a couple of generation techniques for prime numbers. This post is about implementing them.

First implementation of the Sieve of Eratosthenes in JAVA. 334 kata lagi