All Questions
1,636
questions
1
vote
1
answer
128
views
Compute Dickman
Input
A floating point number \$x\$ between 1 and 8 inclusive.
Output
The Dickman function of \$x\$.
The Dickman–de Bruijn function \$\rho(u)\$ is a continuous function that satisfies the delay ...
- 3,106
9
votes
12
answers
691
views
Minimum number of select-all/copy/paste steps for a string containing n copies of the original
This challenge is based on this Mathematics answer.
Write the shortest program or function that, when given some natural number \$n\$, outputs \$S(n)\$, which is the minimum number of steps for ...
- 10.2k
13
votes
9
answers
1k
views
Sum of square roots (as an algebraic number)
An algebraic number is a number that is a root of a non-zero polynomial with integer coefficients. It is well-known that the sum of two algebraic numbers is algebraic. In particular, the sum of a list ...
- 48.7k
3
votes
7
answers
341
views
Find the most isolated point
Given two non-empty sets of points \$P,T = \{(x,y)\ |\ x,y \in \mathbb{Z} \}\$, find the point \$p \in P\$ such that it is the "most isolated" from all points in \$T\$. The "most ...
- 10.2k
13
votes
13
answers
2k
views
Compute the degree of a string
The input is a string made of the letters a,b,c only. The output is an integer representing the degree of the sequence. The degree of a sequence is computed as follows:
Assume that each of the ...
- 1,993
8
votes
4
answers
472
views
How far are you?
Write a program that gets coordinates of two objects on Earth, and calculates how far they are from each other directly in space (a straight line through Earth) and on the surface (through the ...
- 181
13
votes
11
answers
799
views
*Trivial* near-repdigit perfect powers
Task
Output the sequence that precisely consists of the following integers in increasing order:
the 2nd and higher powers of 10 (\$10^i\$ where \$i \ge 2\$),
the squares of powers of 10 times 2 or 3 (...
- 77.5k
16
votes
19
answers
1k
views
Infer pluses and minuses
The problem
Consider an equation such as "3 ± 2 ± 4 ± 1 = 4" and determine if there exists a sequence of pluses and minuses that makes it arithmetically correct. If it exists, ...
- 3,684
26
votes
14
answers
2k
views
Is it a cartesian product?
The cartesian product of two multisets \$A\$ and \$B\$ is the multiset of all ordered pairs consisting of an element of \$A\$ and an element of \$B\$. For example, the cartesian product of \$\{1, 2, 7,...
- 39.2k
10
votes
4
answers
2k
views
Output a 1-2-3-5-7... sequence
Follow-up of my previous challenge, inspired by @emanresu A's question, and proven possible by @att (Mathematica solution linked)
For the purposes of this challenge, a 1-2-3-5-7... sequence is an ...
- 2,093
21
votes
15
answers
2k
views
Output a 1-2-3 sequence
For the purposes of this challenge, a 1-2-3 sequence is an infinite sequence of increasing positive integers such that for any positive integer \$n\$, exactly one of \$n, 2n,\$ and \$3n\$ appears in ...
- 2,093
18
votes
5
answers
3k
views
Draw a Fibonacci Swoosh
Title courtesy of Greg Martin
For this challenge, I'll define an arc of size \$k\$ as a single piece of a sine wave with a length of \$k\$ units and an height of \$\frac{k}{4}\$ units:
And I'll ...
- 39.2k
6
votes
12
answers
946
views
Argument of a complex number (Robbers)
V1.1: Added criterion to help with tiebreakers, a bit overkill but still.V1.2: It's April 15th!
Task: Crack the scrambled code for calculating the argument of a complex number \$z=x+iy\$ given two ...
- 421
11
votes
23
answers
2k
views
Argument of a complex number (Cops)
This is the cop's thread, where one should post the scrambled code. Here is the robbers' thread where the cracked source should be posted and linked to the cop's answer.
NB: I am currently writing up ...
- 421
14
votes
7
answers
2k
views
How quickly can you type this unary string?
If I want to type the string aaa, the least keystrokes I can type it in is 3: a a a. But if I want to type the string ...
- 39.2k