Problems

1 – 45 of 45

Problem Title Likes Solvers Difficulty

Problem 45192. check whether a number is a pentatope number

Created by: Asif Newaz

Tags pentatope

Problem 45191. generate nth pentatope number

Created by: Asif Newaz

Tags number, pentatope

Problem 1407. Is it an Armstrong number?

Created by: Harish Maradana

Tags armstrong no

260

Problem 1012. Determine if input is a perfect number

Created by: Binbin Qi

Tags mod sum, perfect

178

Problem 2061. Narcissistic number ?

Created by: Jean-Marie Sainthillier

Tags narcissistic

280

Problem 44748. Amicable numbers

Created by: cdeliu

Tags number theory, divisors

Problem 1008. Determine if input is a Narcissistic number

Created by: Binbin Qi

Tags mod floor

152

Problem 896. Sophie Germain prime

Created by: Aurelien Queffurust

Tags prime, primes, sophie germain

456

Problem 45223. find nth even fibonacci number

Created by: Asif Newaz

Tags series, number, fibonacci

Problem 45253. Pell numbers

Created by: Asif Newaz

Tags number, sequence, pell

Problem 45250. Be happy

Created by: Asif Newaz

Tags number, happy

Problem 1298. P-smooth numbers

Created by: Richard Zapor

Tags primes, find, mod

Problem 156. Parasitic numbers

Created by: the cyclist

Tags parasitic

268

Problem 2690. Armstrong Number

Created by: VIVEK RUHELA

Tags arithmetic, basic matlab

276

Problem 44385. Extra safe primes

Created by: Matthew Eicholtz

Tags prime numbers, cody5, safe prime

698

Problem 44836. Iccanobif numbers 1

Created by: James

Tags fibonacci, iccanobif

Problem 2733. Evil Number

Created by: Jan Orwat

Tags easy, number theory, oeis

227

Problem 1096. Largest Twin Primes

Created by: Des Mc Manus

Tags primes

388

Problem 45229. Bell Triangle

Created by: Asif Newaz

Tags number, matrix, Magic Numbers

Problem 2593. Polite numbers. N-th polite number.

Created by: Jan Orwat

Tags number theory, a138591

142

Problem 2056. Is this number Munchhausen?

Created by: Ted

Tags math, narcissistic number, munchhausen

163

Problem 44360. Pentagonal Numbers

Created by: goc3

Tags series, number, sequence

616

Problem 525. Mersenne Primes

Created by: Drew Weymouth

Tags math, prime, integers

427

Problem 1804. Fangs of a vampire number

Created by: Andrew Newell

Tags factors, number theory

Problem 166. Kaprekar numbers

Created by: the cyclist

Tags kaprekar

254

Problem 1082. Lychrel Number Test (Inspired by Project Euler Problem 55)

Created by: @bmtran (Bryant Tran)

Tags projecteuler, plus15

Problem 165. Woodall number

Created by: the cyclist

Tags woodall number theory

144

Problem 45194. Cantor counting

Created by: Asif Newaz

Tags cantor, rational number

Problem 45249. Frugal number

Created by: Asif Newaz

Tags number, frugal, economical

Problem 933. Ordinal numbers

Created by: Tim

Tags ordinal, lookup table

156

Problem 2595. Polite numbers. Politeness.

Created by: Jan Orwat

Tags number theory, oeis

139

Problem 1190. Golomb's self-describing sequence (based on Euler 341)

Created by: James

Tags projecteuler, self-referential, golomb sequence

131

Problem 1477. Champernowne Constant

Created by: G K

Tags math

Problem 249. Project Euler: Problem 9, Pythagorean numbers

Created by: Doug Hull

Tags projecteuler

740

Problem 45251. Last non-zero digit

Created by: Asif Newaz

Tags number, factorial

Problem 1925. Smith numbers

Created by: Sky Sartorius

Tags sum, factors

480

Problem 74. Balanced number

Created by: Cody Team

Tags matlab

2359

Problem 1825. Find all vampire fangs

Created by: Andrew Newell

Tags factors, number theory

Problem 1095. Circular Primes (based on Project Euler, problem 35)

Created by: James

Tags primes, projecteuler, circular reasoning

288

Problem 45272. Pseudo-vampire number

Created by: Asif Newaz

Tags numbers, number theory, sequence

Problem 235. Project Euler: Problem 4, Palindromic numbers

Created by: Doug Hull

Tags projecteuler

677

Problem 81. Mandelbrot Numbers

Created by: Cody Team

Tags matlab, fractals

1106

Problem 1826. Find vampire numbers

Created by: Andrew Newell

Tags factors, number theory

277

Problem 1742. Generate a Parasitic Number

Created by: James

Tags parasitic, cyclic

Problem 45274. Fangs of pseudo-vampire number

Created by: Asif Newaz

Tags number theory, vampire

1 – 45 of 45

Difficulty Rating

Problem Groups

Problems