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It is a method for finding the prime and composite numbers
Here is an example of the sieve. Firstly the definition of a prime is a number divisible only by itself and one. From that we can build this sieve, it can of course go on as far as you wish. Though with very large numbers it becomes impractical.
1 2 3 4 5 6 7 89 10 11 12 13 1415 16 17 18 19 20 2122 23 24 25 26 27
Then starting at 1 we highlight all those numbers which can be divided by numbers lower than themselves. Each number in bold is not a Prime number because a number below it can be divided into it with no remainder. Each number in italics is a prime, because, as we have said it can only be divided by 1 and itself. It should also be noted that 2 is the only even prime number, all other even numbers can be divided by 2. So if you are asked if a number is prime and it is an even number then you do not have to check because it is not.
The Sieve of Eratosthenes is a way of determining which numbers are prime.
- Zero and one are, by definition, not prime.
- Write a list of numbers from two up to the highest number in which you are interested.
- The first number, 2, is prime and every multiple of it can not be prime, so cross them out -- that is 4, 6, 8, 10, and so on
- The next number not crossed out will be 3. That is prime but its multiples can't be, so cross them out -- 6, 9, 12, 15, and so on.
- 4 is crossed out, so the next number not crossed out is 5. That is prime, so cross out its multiples, 10, 15, 20, and so on.
- Continue this process until you can not cross out any more numbers (about halfway down the list)
- When you have finished, all numbers not crossed out are prime.
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What best describes the contribution of Eratosthenes?
eratosthenes discovered the circumfrance of the world. he was known as the first successful measurement.
Did Eratosthenes marry?
No.
What is Eratosthenes?
He was an ancient Greek mathematician of the 2nd/3rd century BC, as well as a poet, geographer, musical composer, scholar, and astronomer. He was the first Greek to estimate the circumference and tilt of the earth. He created a map of the earth based on the knowledge available at the time. He was highly respected, and his calculations of the earth's circumference were used for hundreds of years. Today, his method for finding prime numbers from 1-100 is known as the 'Sieve of Eratosthenes' and is taught in math textbooks.
What describes how Eratosthenes discovered the approximate circumference of the earth?
Which of the following describes how Eratosthenes discovered the approximate circumference of the earth
Who was Archimedes' best friend?
Eratosthenes
When did Eratosthenes discover the sieve?
The sieve of Eratosthenes was discovered in 223 BC.
What are you filtering with sieve of eratosthenes?
The Sieve of Eratosthenes filters numbers, letting the composites fall through while the primes remain.
Who created the sieve of eratosthenes?
Eratosthenes, a greek philosopher, did, hence the name.
Where did sieve eratosthenes grow up?
his name isnt sieve but, i know a website all about his life. theres one on eratosthenes on wikipedia. so there, by the way, eratosthenes is the wierdest name ever!!!!!!!!!
What date was Sieve Eratosthenes born?
About 276 BC Eratosthenes was a Greek mathematician who is credited with a simple method of making a list of as many primes as you wish. His method is known as the Sieve of Eratosthenes.
Who invented the prime number sieve?
Eratosthenes
Where did Eratosthenes Sieve invent prime no?
The Sieve did not invent prime numbers. It was used to find them.
How do you pronounce Sieve of Eratosthenes?
era-tos-the- knees.
What did the sieve of Eratosthenes used to find?
prime numbers
When was the sieve of eratosthenes invented?
It was around 200 BC.
How many even prime numbers are there in a sieve of Eratosthenes?
One
Did Eratosthenes have a family?
Yes and his mother and father were part of the family.
