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List the emirps
An emirp is a prime number that becomes a different prime when reversed. The numbers 13, 17, and 149 are emirps, but 11, 19, and...

18 days ago

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Determine whether a prime is Pythagorean

18 days ago

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Compute the nth Pythagorean prime
Pythagorean primes have the form p = 4n+1, where n is an integer, and they can be written as the sum of squares of two integers....

18 days ago

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Largest Twin Primes
<http://en.wikipedia.org/wiki/Twin_prime Twin primes> are primes p1, p2 = p1 + 2 such that both p1 and p2 are prime numbers. Giv...

18 days ago

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Mersenne Primes
A Mersenne prime is a prime number of the form M = 2^p - 1, where p is another prime number. For example, 31 is a Mersenne prim...

18 days ago

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Find nearest prime number less than input number
Find nearest prime number less than input number. For example: if the input number is 125, then the nearest prime number whi...

18 days ago

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Sophie Germain prime
In number theory, a prime number p is a *Sophie Germain prime* if 2p + 1 is also prime. For example, 23 is a Sophie Germain prim...

18 days ago

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Circular Primes (based on Project Euler, problem 35)
The number, 197, is called a circular prime because all rotations of the digits: 197, 971, and 719, are themselves prime. The...

18 days ago

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Mersenne Primes vs. All Primes
A Mersenne prime (M) is a prime number of the form M = 2^p - 1, where p is another prime number. <https://www.mathworks.com/matl...

18 days ago

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The Goldbach Conjecture
The Goldbach conjecture asserts that every even integer greater than 2 can be expressed as the sum of two primes. Given the eve...

18 days ago

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Project Euler: Problem 7, Nth prime
By listing the first six prime numbers: 2, 3, 5, 7, 11, and 13, we can see that the 6th prime is 13. What is the Nth prime numb...

18 days ago

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Factorize THIS, buddy
List the prime factors for the input number, in decreasing order. List each factor only once, even if the factorization includes...

18 days ago

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Find vampire numbers
A vampire number is a number v that is the product of two numbers x and y such that the following conditions are satisfied: at ...

18 days ago

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Get all prime factors
List the prime factors for the input number, in decreasing order. List each factor. If the prime factor occurs twice, list it as...

18 days ago

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Prime factor digits
Consider the following number system. Calculate the prime factorization for each number n, then represent the prime factors in a...

18 days ago

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Number of Even Elements in Fibonacci Sequence
Find how many even Fibonacci numbers are available in the first d numbers. Consider the following first 14 numbers 1 1 2...

18 days ago

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Fibonacci-Sum of Squares
Given the Fibonacci sequence defined by the following recursive relation, * F(n) = F(n-1) + F(n-2) * where F(1) = 1 and F(1)...

18 days ago

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Find the next Fibonacci number
In the sequence of Fibonacci numbers, every number is the sum of the two preceding ones: 1, 1, 2, 3, 5, 8, 13, 21, 34, 55...

18 days ago

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Fibonacci sequence
Calculate the nth Fibonacci number. Given n, return f where f = fib(n) and f(1) = 1, f(2) = 1, f(3) = 2, ... Examples: Input...

18 days ago

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Half-Swap
Given a vector with an even number of elements, rearrange it so that the elements in its first half are switched with those i...

18 days ago

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Matlab Basics - Switching Assignments
Switch assignments for variables x and y, for example start with x = 1 and y = 3 end with y = 1 and x = 3 Do NOT simply r...

18 days ago

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Swap between columns
The idea is to swap between second and second last column Ex = [1 2 3 4 5; 1 2 3 4 5; 1 2 3 4 5; 1 2 3 4 5; ...

18 days ago

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Remove a specific character with another
Remove any (-) dash sign with (_) underscore Ex = 'The-Journey-of-thoudsands-miles-starts-with-a-single-step' y = 'The_Jour...

18 days ago

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Swap between first and last
The idea is to swap between first and last row Ex = [1 2 3 4 5; 1 2 3 4 5; 1 2 3 4 5; 1 2 3 4 5; ...

18 days ago

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Swap between first and last column
The idea is to swap between first and last column Ex = [1 2 3 4 5; 1 2 3 4 5; 1 2 3 4 5; 1 2 3 4 5; 1 2 3 ...

18 days ago

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Swap between rows
The idea is to swap between second and second last row Ex = [1 2 3 4 5; 5 4 3 2 1; 1 2 3 4 5; 1 2 3 4 5; ...

18 days ago

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Stress-Strain Properties - 1
This is the first in a series of problems regarding mechanics of materials, in particular, material properties drawn from stress...

25 days ago

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Find Logic 15

25 days ago

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remove every row&col for every nan
for a given matrix, remove the row and column of every nan. Example x=[1 2 NaN 4 5 6 7 8 ...

1 month ago

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Remove all the columns contains only zero
Remove the column from the matrix which has only zeros . Refer the Example below a= 1 0 3 0 23 0 56 0 1 ...

1 month ago