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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.
Laverna Schroeder
The sieve of Eratosthenes is an ancient algorithm used to find all prime numbers up to a given limit. It works by iteratively marking the multiples of each prime number starting from 2, effectively crossing out all composite numbers, until only prime numbers remain. The remaining unmarked numbers are then considered prime.
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What are you filtering with sieve of eratosthenes?
The Sieve of Eratosthenes filters numbers, letting the composites fall through while the primes remain.
Why do you think this grid is called a sieve?
Yes
What is the difference between sift and sieve?
STRAIN - separate solid from liquid to pour food, etc. through something with very small holes in it, for example a SIEVE, in order to separate the solid part from the liquid part. SIFT to remove something that you do not want from a substance by putting it through a SIEVE: E.g.: Put the flour through a sieve to sift out the lumps. SIEVE a tool for separating solids from liquids or larger solids from smaller solids, made of a wire or plastic net attached to a ring.
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
What is the difference between a wet sieve and a dry sieve analysis?
What is the difference between a wet sieve and a dry sieve
Who made the sieve?
Forrest Sieve
What is sentence of sieve?
You can sift flour using a sieve.
What does sieve meen?
A sieve is a very fine screen used to filter, or sieve, solids out of liquids.
What the conclusion the sieve analysis?
the importance of sieve analysis
What is the difference between wet and dry sieve analysis?
wet sieve analysis is wetdry sieve analysis is dry
What is 3 to 4 sieve green bean mean?
what is bigger a 3 sieve or 4 sieve green bean
What is the noun form of sieve?
The word sieve is a noun as well as a verb (sieve, sieves, sieving, sieved); example uses: Noun: The sieve to strain the spaghetti is in that cupboard. Verb: I don't sieve the mashed potatoes, I like them a bit lumpy.
What is a use of a sieve?
the use of a sieve is to get rid of lumps =D
When was Nectar in a Sieve created?
Nectar in a Sieve was created in 1954.
What is a sieve phloem?
The cells having sieve like perforations in their cell walls present in phloem are the sieve tubes of the phloem.
Are used for what in a sieve which size plates?
Sieve plates are cross walls separating the cells in the phloem and have lots of minute pores. These cross-walls look like a sieve and so are called sieve plates. The holes in the sieve plates allows rapid flow of manufactured food substances through the sieve tubes.
