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Tag Archives: primes
Find Mersenne primes in C#
Mersenne primes are prime numbers of the from 2n – 1 for some integer n. For example, 22 – 1 = 4 – 1 = 3 and 3 is prime, so 3 is a Mersenne prime. This example uses a … Continue reading
Posted in algorithms, mathematics
Tagged algorithms, C#, C# programming, example, example program, mathematics, Mersenne primes, prime numbers, primes, Windows Forms programming
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Use PLINQ to select prime numbers from an array in C#
The example Use PLINQ to select even numbers from an array in C# uses PLINQ (Parallel LINQ) to find the even numbers in an array of random values. This example uses a similar technique to do something slightly more interesting: … Continue reading
Find random prime numbers in C#
The example Probabilistically determine whether a number is prime in C# explains an algorithm for determining whether a number is prime with any desired level of certainty. After you add that method to your algorithmic toolkit, finding large prime numbers … Continue reading
Determine whether a number is prime in C#
This is a cool little algorithm that uses some clever mathematics. This algorithm and several related algorithms are described in my book Essential Algorithms: A Practical Approach to Computer Algorithms. I think it’s a really good book (and it’s gotten … Continue reading
Use yield to generate prime numbers in C#
This example is based on a lesson about interfaces that I recently recorded for O’Reilly Video Training. This example shows how to use the yield return statement to generate prime numbers. More importantly it explains how yield return … Continue reading
Draw a colored fractal curve generated by prime numbers in C#
This example shows how to draw a colored fractal curve generated by prime numbers. See the example Draw a fractal curve generated by prime numbers in C# for the basic algorithm. This example assigns colors to line segments based on … Continue reading
Posted in algorithms, fractals, graphics, mathematics
Tagged algorithms, C#, C# programming, color, colored fractal, example, example program, fractal curve, fractals, graphics, mathematics, prime numbers, primes, Windows Forms programming
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Draw a fractal curve generated by prime numbers in C#
This example shows how to draw a fractal curve generated by prime numbers. It’s a modification of the earlier example Draw a fractal generated by prime numbers in C#. The basic idea is follow these rules: Start at the point … Continue reading
Posted in algorithms, fractals, graphics, mathematics
Tagged algorithms, C#, C# programming, example, example program, fractal curve, fractals, graphics, mathematics, prime numbers, primes, Windows Forms programming
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Use a bitmap to visualize composite runs in C#
I promise this is my last post on primes for a while. (Sometimes one example leads to another, which leads to another, and so on.) This example draws a bitmap to help visualize composite runs and prime numbers. The basic … Continue reading
Find runs of composite numbers (nonprimes) in C#
I recently had a birthday and my age is a prime number, so like any normal person I was wondering how long a run of consecutive composite numbers comes after my current age. (Doesn’t everyone wonder such things?) This example … Continue reading
Use a bitmap to visualize odd primes in C#
This example modifies the program in Use a bitmap to visualize primes in C# to let you visualize odd primes. It creates an is_prime array like the previous example does, but it makes the array twice as large as before. … Continue reading