Solved

Square Digits Number Chain Terminal Value (Inspired by Project Euler Problem 92)
Given a number _n_, return the terminal value of the number chain formed by summing the square of the digits. According to the P...

23 days ago

Solved

Return the Fibonacci Sequence
Write a code which returns the Fibonacci Sequence such that the largest value in the sequence is less than the input integer N. ...

23 days ago

Solved

Integer Sequence - II : New Fibonacci
Crack the following Integer Sequence. (Hints : It has been obtained from original Fibonacci Sequence and all the terms are also ...

23 days ago

Solved

Golomb's self-describing sequence (based on Euler 341)
The Golomb's self-describing sequence {G(n)} is the only nondecreasing sequence of natural numbers such that n appears exactly G...

23 days ago

Solved

nth Rational Number
Return the nth rational number. This is the inverse to Problem 1471. Index of a Rational number The first ten positive rationa...

24 days ago

Solved

Armstrong Number
Determine whether the given input n-digit number is Armstrong Number or not. Return True if it is an Armstrong Number. An n-Dig...

25 days ago

Solved

Longest Collatz Sequence
Inspired by Projet Euler n°14. The Collatz iterative sequence (See Cody problem n° 2103 and 211) is defined for the set of po...

25 days ago

Solved

Highly divisible triangular number (inspired by Project Euler 12)
Triangular numbers can be calculated by the sum from 1 to n. For example, the first 10 triangular numbers are: 1, 3, 6, 10, ...

25 days ago

Solved

Compute Fibonacci Number
Compute the n-th Fibonacci Number f(0) = 0, f(1) = 1, f(2) = 1, f(3) = 2, ... f(42) = 267914296

25 days ago

Solved

Find the 9's Complement
Find the 9's complement of the given number. An example of how this works is <http://electrical4u.com/9s-complement-and-10s-c...

25 days ago

Solved

Prime Ladders
A <http://en.wikipedia.org/wiki/Word_ladder word ladder> transforms one word to another by means of single-letter mutations. So ...

25 days ago

Solved

Circular Primes (based on Project Euler, problem 35)
The number, 197, is called a circular prime because all rotations of the digits: 197, 971, and 719, are themselves prime. The...

26 days ago

Solved

Amicable numbers
Test whether two numbers are <https://en.wikipedia.org/wiki/Amicable_numbers amicable>, meaning that the sum of the proper divis...

26 days ago

Solved

Woodall number
Test whether the input is a Woodall number: <http://en.wikipedia.org/wiki/Woodall_number> _Please do not cheat by simply chec...

26 days ago

Solved

Fangs of pseudo-vampire number
given a number, find all the fangs of that number. A pseudo-vampire number can have multiple of fangs. The output should be a...

26 days ago

Solved

find nth even fibonacci number
1st even fibonacci number=2 ; 2nd even fibonacci number=8 ..

26 days ago

Solved

Cantor counting
Find the nth cantor's rational number. the sequence is given below in the link. Sequence: 1/1,1/2,2/1,3/1,2/2,1/3,1/4... ... .....

26 days ago

Solved

The Tortoise and the Hare - 01
Suppose in an infinitely long line, the hare is standing in position 0. From that place, it can jump either in the +ve direct...

26 days ago

Solved

Project Euler: Problem 10, Sum of Primes
The sum of the primes below 10 is 2 + 3 + 5 + 7 = 17. Find the sum of all the primes below the input, N. Thank you <http:/...

27 days ago

Solved

Project Euler: Problem 8, Find largest product in a large string of numbers
Find the greatest product of five consecutive digits in an n-digit number. 73167176531330624919225119674426574742355349194934...

27 days ago

Solved

Project Euler: Problem 6, Natural numbers, squares and sums.
The sum of the squares of the first ten natural numbers is, 1^2 + 2^2 + ... + 10^2 = 385 The square of the sum of the first ...

27 days ago

Solved

Project Euler: Problem 4, Palindromic numbers
A palindromic number reads the same both ways. The largest palindrome made from the product of two 2-digit numbers is 9009 = 91 ...

27 days ago

Solved

Project Euler: Problem 7, Nth prime
By listing the first six prime numbers: 2, 3, 5, 7, 11, and 13, we can see that the 6th prime is 13. What is the Nth prime numb...

27 days ago

Solved

Project Euler: Problem 2, Sum of even Fibonacci
Each new term in the Fibonacci sequence is generated by adding the previous two terms. By starting with 1 and 2, the first 10 te...

27 days ago

Solved

Find all vampire fangs
A vampire number is a number v that is the product of two numbers x and y such that the following conditions are satisfied: at ...

27 days ago

Solved

Be happy
check whether the given number is happy in b-base. * A happy number can be defined as a number which will yield 1 when it is ...

29 days ago

Solved

Pernicious Anniversary Problem
Since Cody is 5 years old, it's pernicious. A <http://rosettacode.org/wiki/Pernicious_numbers Pernicious number> is an integer w...

29 days ago

Solved

Recaman Sequence - II
Take an arbitrary starting point as input and create Recaman Sequence. Then find the 1, return its index. For example: if n =...

29 days ago

Solved

Pi Digit Probability
Assume that the next digit of pi constant is determined by the historical digit distribution. What is the probability of next di...

29 days ago

Solved

Narcissistic number ?
Inspired by Problem 2056 created by Ted. In recreational number theory, a narcissistic number is a number that is the sum of ...

29 days ago