Hello World

The most simple of Python programs.

12

Sum in Array

The sum of all numbers in array [x, y, x] is equal to x + y + z

11

Exponentiation

Exponentiation is a mathematical operation written as \(a^n\), which means multiply \(a\) by...

13

Coordinates

Starting from the point (0,0) on a grid, you are given a set of instructions:

^ = Up one unit

v (lowercase v) =...

9

Elevator

An elevator is given an input code which it then uses to go up or down floors:

"^" = go up one floo...

9

Collatz conjecture

Start with any positive integer \(n\). Then each term is obtained from the previous term as follows: if the...

18

Caesar Cipher

A caesar cipher is a substituion cipher in which each letter in the plaintext is replaced by a letter some fixed...

3

Product in Array

The product of array [x, y, z] is equal to \(x \times y \times z\)

3

Sum of primes

A prime is an integer, greater than 1, which is divisible only by itself and 1.

For example the first 5 primes are: ...

4

Find the hidden message!

Each letter of the english alphabet is corresponding to an integer number.

a = 1, b = 2, ... , z = 26

For a giv...

3

Sum of Powers

Given an array, a machine outputs the sum of every other digit to the power of the next digit.

For example:

Giv...

2

Factorial

The factorial of a non-negative integer n, denoted by n!, is the product of all po...

7

Sum of Primes in Array

A prime is an integer, greater than 1, which is divisible only by itself and 1.

For example the first 5 primes are...

3

Prime Fibonacci Sequence

In the fibonacci sequence every number is the sum of the two preceding ones:

\(1, 1, 2, 3, 5, 8, 13, 21, 3...

2

Ruth–Aaron pair

A Ruth-Aaron pair consists of two consecutive integers (e.g. 714 and 715) for which the sums of the prime factors of ...

7

Munchhausen Number

A Munchhausen number is a number, which is the sum of it's digits raised to themselves.

One Munchhausen number i...

1

Index of coincidence

The index of coincidence provides a measure of how likely it is to draw two matching letters by randomly selecting tw...

1

Factorial II

In mathematics, the factorial of a non-negative integer \(n\), denoted by \(n!\), is the&nbs...

3

Least common multiple

The least common multiple of some integers is usually written as \([a,b,...]\) or \(lcm(a,b,...)\), wh...

1

ASCII converting

For some reason the first post about this did not include the actual text to decrypt. Here is the problem again:

&...

2

Appending digits

\(a\) is formed by appending the digit 1 to the front of an integer.

\(b\) is formed by appending the digi...

1

Relatively prime integers

Two integers \(a\) and \(b\) are said to be relatively prime if the only positive integer that divides both...

1

Lychrel Numbers

The Lychrel number algorithm is defined as follows: Starting with a positive integer perform the iterative process of...

2

Radix

In mathematical numeral systems, the **radix** or **base** is the number of unique digits, incl...

1

Smallest 12345 prime

A 12345 is a prime is a prime number which contains the digits 12345 (in that order).

A prime number is a number t...

1

Very Stupid Numbers

For some integer \(n\), let \(D_{n_1}=n\) and for \(i>1\), let \(D_{n_i}\) be the s...

5

Sum

1+3

0

The "x2" question

Set function \(m(n) =\) move the last digit of n to the first digit.

For example:

\(m(126) = 612\)

\(m(2017)...

4

Hexadecimal Mirror Number

Let's call the number you get from writing all its digits reversed its mirror number, eg the mirror number o...

1

Minimal sigma-totient product

For a positive integer \(n\), let \(\phi (n)\) be the number of integers less than \(n\) tha...

3

Huffman Decoding

A string was compressed using the following Huffman bit code table:

Symbol | Bit C... |
---|

1

Kaprekar's Constant

Kapreka's Constant is 6174. When you sort its digits once in ascending and once in descending order you get ...

1

Ascending Numbers

An ascending number is a positive integer of two or more digits such that every digit is greater then the digits that...

4

Special Numbers

A number *N *is considered special if for *N = k/d(k)*, where *d(k)* is the number of divisors of&...

3

make a simple program

0

Transitive subsets

Let \(V_0 = \varnothing\) be the empty set and for \(i>0\), let \(V_i = \mathcal{P}(V_{i-1})\)...

3

Hello world

this is an easy question for beginners

0

0

periodic cycle lengths

Any rational number \(a/b\) can be written as a decimal expansion which either is finite or has a period, a recu...

3

One Time Pad Cipher

The One Time Pad cipher is a method of encrypting alphabetical messages.

It works by converti...

1

Modded File

0

Generic Double Ended Queue

Deque or Double Ended Queue is a generalized version of Queue data structure that allows insert and de...

0

coding

adding of two numbers

0

Highly Composite

A highly composite number is a number with more factors than any of the previous numbers before it. A simple list of ...

0

cccccxx

xcxzc

0

TestProblem

Do stuff

0