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Outer product of multiple vectors
In tensor algebra, it is often useful to define a tensor as a product of lower order tensors. Similarly, a multidimensional arra...

10 months ago

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Combined Ages 4 - Non-symmetric with multiples, n ≥ 3
This problem is slightly more difficult than <http://www.mathworks.com/matlabcentral/cody/problems/42383-combined-ages-3-non-sym...

10 months ago

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Nilpotent matrix
Check if matrix A is <http://mathworks.com/ nilpotent>.

10 months ago

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linear least squares fitting
Inputs: * |f|: cell-array of function handles * |x|: column vector of |x| values * |y|: column vector of |y| values, same l...

10 months ago

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System of equations
Find a solution to a system of equations represented by a |n| by |n+1| matrix. For instance, [ 2 0 4; => 2*x = 4 ...

10 months ago

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Combined Ages 2 - Symmetric, n ≥ 3
Following on <http://www.mathworks.com/matlabcentral/cody/problems/42382-combined-ages-1-symmetric-n-3 Combined Ages 2>, you wil...

10 months ago

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Is this matrix orthogonal?
Given a square matrix, a, determine whether it is orthogonal. INPUT: a, a n x n matrix OUTPUT: true or false

10 months ago

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Orthonormal matrix
You decide whether any given matrix is an orthonormal matrix or not. If each column in a matrix is perpendicular to the other...

10 months ago

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Projector Matrix
Write a function to determine whether or not the matrix is a projector. Projector matrices are defined as P^2 = P.

10 months ago

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Combined Ages 1 - Symmetric, n = 3
You have probably seen the common riddle wherein combined ages are provided and you must determine the individual ages. For exam...

10 months ago

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Solve the set of simultaneous linear equations
Given this pair of simultaneous linear equations: 2x + 3y = 23 3x + 4y = 32 Find the solution set (x,y)

10 months ago

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Column norms of a matrix
Given a matrix M, return a vector y such that for each k y(k)=norm(M(:,k)) (y(k) is the Euclidean norm of the k-th col...

10 months ago

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Linear system of equations
Solve the system of equations in three variables.

10 months ago

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List the good primes
The th prime is classified as “good” if for . For example, 5 is a good prime because is greater than and , but 7 is not beca...

10 months ago

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List Proth primes

10 months ago

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Determine whether a number is a prime self number
Integers can be classified as generated numbers or self numbers. A generated number is one that can be expressed as the sum of a...

10 months ago

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Compute home primes in a given base

10 months ago

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List the delete-a-digit primes

10 months ago

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Count the primes in Collatz sequences
Several Cody problems (21, 69, 42937, 44448, 44784, 52422) involve Collatz sequences. These start with a seed . If is odd, the ...

10 months ago

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Solve the arithmetic differential equation D(n) = n

10 months ago

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Compute the arithmetic derivative of integers

10 months ago

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Label primes with the Erdos-Selfridge classification

10 months ago

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Find pairs of primes with the same digit sum and a specified separation

10 months ago

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Identify prime words

10 months ago

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Determine whether a number is unprimeable
The number 204 is unprimeable because no single digit can be changed to make it prime. In contrast, the number 207 is not unprim...

10 months ago

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List Honaker primes
The number 131 is the 32nd prime number. It is a Honaker prime because the sum of its digits (1+3+1) equals the sum of the digit...

10 months ago

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Classify product/digit-sum sequences
Cody Problem 53120 involved a sequence in which a term is computed by multiplying the previous two terms and adding the digits o...

10 months ago

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List prime anagrams of a number

10 months ago

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Iterate the sum of divisors and totient

10 months ago

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Compute a determinant
Write a function to compute the determinant of an x matrix with diagonal entries equal to an integer and other entries equal ...

10 months ago