Questions tagged [math]
The challenge involves mathematics. Also consider using more specific tags: [number] [number-theory] [arithmetic] [combinatorics] [graph-theory] [geometry] [abstract-algebra].
23
votes
16answers
555 views
Custom Number Base Converter
The powers that be want to be able to quickly convert any number they have into their own number base using any format they would like.
Input
Your program must accept 3 parameters.
Number: The ...
7
votes
11answers
199 views
Construct a line graph / conjugate graph
Introduction
Given an undirected graph G, we can construct a graph L(G) (called the line graph or conjugate graph) that represents the connections between edges in G. This is done by creating a new ...
21
votes
17answers
1k views
RTA (Reverse-Then-Add) root of a number
The reverse-then-add (RTA) sequence is a sequence obtained by adding a number to its reverse, and repeating the process on the result. For eg.,
$$ 5 + 5 = 10 \Rightarrow 10 + 01 = 11 \Rightarrow 11 +...
-3
votes
1answer
117 views
number decomposition [duplicate]
It's been a while since I posted here, so here we go another day another challenge.
Challenge :
Given a number(n) split it into it's prime factors.
Input :
A ...
0
votes
1answer
97 views
Symmetric Numbers [duplicate]
write a function to tell if a number is symmetric or not.
for example:
input:
151
output:
True
input:
142
output:
False
and so on:
1111 True,
2390 False,
1226221 True
17
votes
34answers
909 views
Calculate power series result [duplicate]
Related: Calculate Power Series Coefficients
Given a positive integer \$X\$ and a max exponent (Also a positive integer too) \$N\$ calculate the result of a power series. Example:
$$X^0+X^1+X^2+\...
18
votes
28answers
2k views
Count the lucky tickets within the given range
In Russia we have something like a tradition: we like to look for lucky tickets.
Here's what a regular ticket looks like:
As you can see, the ticket has a six-digit number.
A six-digit number is ...
22
votes
16answers
3k views
Find the inverse of a 3 by 3 matrix
Challenge
Given nine numbers, a, b, c, d, e, f, g, h, i, as input which correspond to the square matrix:
$$\mathbf{M} = \begin{pmatrix}a& b& c\\ d& e&...
14
votes
14answers
1k views
Exact Partial Sum of Harmonic Series
Challenge
Given a positive integer N, output the sum of the first N reciprocals as an exact fraction, which is represented as a ...
6
votes
11answers
389 views
Draw a times table (also called modular multiplication circle) of a number \$n\$ with \$k\$ vertices
Not to be confused with this question.
You need to draw a times table (also known as Cremona's method for cardioid generation) as shown in this video. The number \$n\$ and \$k\$ will be the inputs.
...
19
votes
2answers
369 views
Existential Golf
Math has a lot of symbols. Some might say too many symbols. So lets do some math with pictures.
Lets have a paper, which we will draw on. To start the paper is empty, we will say that is ...
-6
votes
15answers
294 views
Perfect Squares below \$n\$
A perfect square is an integer that is the square of an integer; in
other words, it is the product of some integer with itself.
Calculate the number of perfect squares below a number \$n\$ where \$...
11
votes
39answers
4k views
Last digit large number
For a given list of number \$[x_1, x_2, x_3, ..., x_n]\$ find the last digit of \$x_1 ^{x_2 ^ {x_3 ^ {\dots ^ {x_n}}}}\$
Example:
...
21
votes
2answers
543 views
Double a number's continued fraction
Your task is, given x, output 2*x. Easy right!? But there's a catch: x will be given as a (...
19
votes
34answers
2k views
Find the Squarish Root
Write code that when given a positive number \$x\$ as input, outputs the largest positive divisor of \$x\$ less than or equal to the square root of \$x\$.
In other words find the largest \$n > 0\$ ...
24
votes
17answers
2k views
Integers sorted by their digital roots
The digital root (also repeated digital sum) of a positive integer is the (single digit) value obtained by an iterative process of summing digits, on each iteration using the result from the previous ...
19
votes
44answers
2k views
count ones in range
Challenge :
Count the number of ones 1 in the binary representation of all number between a range.
Input :
Two non-decimal positive integers
Output :
The sum ...
2
votes
2answers
371 views
Which number is bigger?
Define f(a,b) := a if b=1; a^f(a,b-1) if b>1 (Tetration, where ^ means power) for positive integers ...
18
votes
19answers
2k views
Evaluate polynomial expression string
Create a function which takes a polynomial equation, a value for x and returns the result of the operation.
Example: given ...
-1
votes
11answers
219 views
Smallest possible version of abs [duplicate]
The abs() function in most languages does one thing: give the positive version of the input. Most of the times this is done using something similar to
...
10
votes
22answers
1k views
Cartesian product of a list with itself n times
When given a a list of values and a positive integer n, your code should output the cartesian product of the list with itself n ...
11
votes
12answers
818 views
Sum of replicated matrices
Given a list of numbers [ a1 a2 ... an ], compute the sum of all the matrices Aᵢ where Aᵢ is defined as follows (m is the maximum of all aᵢ):
...
3
votes
0answers
182 views
Mathematical parser [duplicate]
Challenge :
Given a string representing a mathematical expression return the result
Input :
A string representing a mathematical expression : ...
3
votes
0answers
155 views
Make Three from One [duplicate]
Given a single digit integer and a three digit integer, output a mathematical formula that uses only the single digit and a given list of operators to equal the three digit integer.
Input: A one ...
-1
votes
1answer
181 views
Find the longest uninterrupted arc in N dimensions
See similar question for 2D case: Find the longest uninterrupted arc
The challenge here is to find the longest uninterruped great circle arc around a unit hypersphere in N dimensions, with a random ...
5
votes
3answers
323 views
Find the longest uninterrupted arc
The challenge here is to find the longest uninterruped arc around a unit circle with a random amount of points distributed in random positions around it.
Here is a diagram to assist my explanation:
...
20
votes
5answers
1k views
Golfing out the haters
The setup:
A social network reports the number of votes a post has in two ways: the number of net upvotes (total upvotes - total downvotes), and the % of votes that were upvotes, rounded to the ...
24
votes
34answers
2k views
Sign-Swapping Sums
Given a nonempty list of positive integers \$(x, y, z, \dots)\$, your job is to determine the number of unique values of \$\pm x \pm y \pm z \pm \dots\$
For example, consider the list \$(1, 2, 2)\$. ...
16
votes
7answers
995 views
Nim Multiplication
Background
If you do much code golfing, you're likely aware of the bitwise XOR operation. Given two integers, it gives another integer with 1s in the bits where ...
51
votes
11answers
3k views
Bringing a pair of integers to equality
This was inspired by a math problem I saw somewhere on the internet but do not remember where (UPDATE: The original problem was found on the math riddles subreddit with a proof provided that it is ...
36
votes
1answer
604 views
What's in my pasta sauce?
Background
In France, and probably in the rest of the European Union, any food available for sale must list the ingredients that compose it on its packaging, in weight percentage descending order. ...
14
votes
25answers
2k views
Prime or highest factor
Challenge:
Given an array of non-negative whole numbers numbers in the range of 0 to Infinity, Check whether all of them are primes or not. (You can take input as ...
16
votes
21answers
2k views
Is this a staircase number?
Challenge :
Check if the given number forms a number staircase or not
Input :
A integer (greater than 0 and not decimal). NOTE : You can take input as string , ...
-4
votes
53answers
756 views
Return the highest possible placement value based on the input
Introduction
The challenge itself was something I came across and had to try and figure out for a personal of project of mine. I ended up branching out and asking family members if they could provide ...
29
votes
12answers
1k views
Triangular Lattice Points close to the Origin
Background
A triangular grid is a grid formed by tiling the plane regularly with equilateral triangles of side length 1. The picture below is an example of a triangular grid.
A triangular lattice ...
8
votes
24answers
1k views
Golf me the Schlosberg Numbers
Schlosberg Numbers
In issue 5 of Mathematical Reflections, Dorin Andrica proposed the problem of characterising the positive integers n such that is an even integer. Eight people submitted ...
-5
votes
19answers
251 views
Sum power of digits
Challenge :
Given two non-negative integers (X and Y > 1) calculate the sum of digits of their powers . i.e : sum of digits of ...
10
votes
10answers
961 views
Am I a Pillai prime?
A Pillai prime is a prime number \$p\$ for which there exists some positive \$m\$ such that \$(m! + 1) \equiv 0 \:(\text{mod } p)\$ and \$p \not\equiv 1\:(\text{mod }m)\$.
In other words, an ...
12
votes
25answers
2k views
Simple golfing interpreter
Challenge:
Your job is to create a simple interpreter for a simple golfing language.
Input:
Input will be in the form of string separated by spaces.
You can replace space separation with what you ...
43
votes
41answers
5k views
Detect heat waves
Background
The Royal Netherlands Meteorological Institute defines a heat wave* as a series of at least 5 consecutive days of ≥25°C weather (“summery weather”), such that at least 3 of ...
5
votes
27answers
1k views
Simple Factorial Challenge [duplicate]
In light of today's date...
A factorial of a number n, is the product of all the numbers from 1 to n inclusive.
The Challenge
Given an integer n where 0 <= n <= 420, find the sum of the ...
18
votes
13answers
2k views
Conway's Prime Game
Specifically, Conway's PRIMEGAME.
This is an algorithm devised by John H. Conway to generate primes using a sequence of 14 rational numbers:
...
9
votes
44answers
3k views
Integer logarithms
Given integers N , P > 1 , find the largest integer M such that P ^ M ≤ N.
I/O:
Input ...
11
votes
3answers
408 views
Polynomial -> Integrate
Given a polynomial in one variable with rational coefficients, output an equivalent expression containing only 1, variables, and definite integrals. For example, -...
5
votes
17answers
803 views
Solve for N from input string
Challenge :
Your job is to find the given number N.
Input :
You will be given a string in the following form:
dN ± Y = X
...
17
votes
26answers
1k views
Rotational Average
Given an input integer n >= 10, output the average of all deduplicated rotations of the integer.
For example, for input 123, ...
13
votes
12answers
714 views
Circle intersection area
Description :
Given x and y positions of two circles along with their radii, output the ...
3
votes
2answers
67 views
Generate lowest degree polynomial from sequence [duplicate]
Introduction
A sequence of numbers is passed in as the input. The program has to generate the lowest degree polynomial possible. This was my first programming project in college and it would be ...
22
votes
17answers
1k views
Generate a Walsh Matrix
A Walsh matrix is a special kind of square matrix with applications in quantum computing (and probably elsewhere, but I only care about quantum computing).
Properties of Walsh matrices
The ...
-6
votes
20answers
528 views
XOR reduction bools
Description :
Given a string of space separated binary digits or space separated booleans or an array of binary digits or array of booleans . Your job is to find the xor of each until you end up with ...
