Community Profile

# Jan Olsen

##### Last seen: 3 days ago
304 total contributions since 2020

View details...

Contributions in
View by

Solved

Generalised Hamming Number
Inspired by Project Euler n°204 and Problem 1308 by James A generalised Hamming number of type n, has no prime factor larger ...

4 months ago

Solved

Smith numbers
Return true if the input is a Smith number in base ten. Otherwise, return false. Read about Smith numbers at <http://en.wikipedi...

4 months ago

Solved

Proper Factors
Generate the proper factors of input integer _x_ and return them in ascending order. For more information on proper factors, ref...

4 months ago

Solved

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

4 months ago

Solved

Numbers with prime factors 2, 3 and 5.
Make a function which takes one positive integer n and returns a matrix with the numbers of the form (2^i)*(3^j)*(5^k) which are...

4 months ago

Solved

Multiples of a Number in a Given Range
Given an integer factor _f_ and a range defined by _xlow_ and _xhigh_ inclusive, return a vector of the multiples of _f_ that fa...

4 months ago

Solved

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...

4 months ago

Solved

Project Euler: Problem 16, Sums of Digits of Powers of Two
2^15 = 32768 and the sum of its digits is 3 + 2 + 7 + 6 + 8 = 26. What is the sum of the digits of the number 2^N? Thanks ...

5 months ago

Solved

It's going down. We're finding simbers!
This problem is inspired by Project Euler 520: Simbers. "We define a simber to be a positive integer in which any odd digit, ...

5 months ago

Solved

Large Sum (inspired by Project Euler 13)
Your function will be provided an arbitrary number of numbers of arbitrary sizes as a cell array of strings. Some numbers will b...

5 months ago

Solved

Hexagonal numbers on a spiral matrix
Put hexagonal numbers in a ( m x m ) spiral matrix and return the sum of its diagonal elements. Formula of hexagonal numbers ...

5 months ago

Solved

Divisible by 13
Write a function to determine if a number is divisible by 13. Similar to the number seven, this can be done by a few different m...

5 months ago

Solved

Sums of cubes and squares of sums
Given the positive integers 1:n, can you: 1. Compute twice the sum of the cubes of those numbers. 2. Subtract the square...

5 months ago

Solved

Sum of big primes without primes
Inspired by Project Euler n°10 (I am quite obviously a fan). With problem n°250 by Doug, you can find some global methods to ...

5 months ago

Solved

Infinite precision division
Develop a function that will divide a very very large integer numerator, supplied to function as a string (e.g., '12233344445555...

5 months ago

Solved

How to multiply?
* Imagine you are in 3012 Anno Domini, when everyone must learn how to multiply, * and competing for the highly prestigious pos...

5 months ago

Solved

How to subtract?
*&plusmn &plusmn &plusmn &plusmn &plusmn &plusmn &plusmn &plusmn &plusmn &plusmn &plusmn* * Imagine you need to subtract one...

5 months ago

Solved

* Imagine you are in 2222 Anno Domini, when everyone must learn how to add, * and competing for the highly prestigious post of,...

5 months ago

Solved

Reindex a vector
You are given two vectors of equal length. Vector N has numeric values (no Inf or NaN) while vector IDX has integers. Place th...

5 months ago

Solved

Remove the two elements next to NaN value
The aim is to *remove the two elements next to NaN values* inside a vector. For example: x = [6 10 5 8 9 NaN 23 9 7 3 21 ...

5 months ago

Solved

Joining Ranges
You are given a n-by-2 matrix. Each row represents a numeric range, e.g. x = [0 5; 10 3; 20 15; 16 19; 25 25] contains...

5 months ago

Solved

Getting logical indexes
This is a basic MATLAB operation. It is for instructional purposes. --- Logical indexing works like this. thresh = 4...

5 months ago

Solved

Set the array elements whose value is 13 to 0
Input A either an array or a vector (which can be empty) Output B will be the same size as A . All elements of A equal to 13...

5 months ago

Solved

Getting the indices from a matrice
Getting the indices from a matrice. Inspired by Problem 645. Getting the indices from a vector by the great Doug Hull. Given a...

5 months ago

Solved

Fill a zeros matrix
The aim is to fill an array of all zeros given a numerical value and the index of row and columns for this value. 3 Inputs: ...

5 months ago

Solved

Get the elements of diagonal and antidiagonal for any m-by-n matrix
In the problem <http://www.mathworks.com/matlabcentral/cody/problems/858-permute-diagonal-and-antidiagonal Problem 858. Permute ...

5 months ago

Solved

Replicate elements in vectors
Replicate each element of a row vector (with NaN) a constant number of times. Examples n=2, A=[1 2 3] -> [1 1 2 2 3 3] ...

5 months ago

Solved

First non-zero element in each column
For a given matrix, calculate the index of the first non-zero element in each column. Assuming a column with all elements zero ...

5 months ago

Solved

Create logical matrix with a specific row and column sums
Given two numbers *|n|* and *|s|*, build an |n-by-n| logical matrix (of only zeros and ones), such that both the row sums and th...

6 months ago

Solved

Generate N equally spaced intervals between -L and L
Given N and L, return a list of numbers (in ascending order) that divides the interval [-L L] into N equal-length segments. F...

6 months ago