Problems

1 – 35 of 35

Problem Title Likes Solvers Difficulty

Problem 2056. Is this number Munchhausen Narcissistic?

Created by: Ted

Tags math, narcissistic number, munchhausen

146

Problem 45253. Pell numbers

Created by: Asif Newaz

Tags number, sequence, pell

Problem 45229. Bell Triangle

Created by: Asif Newaz

Tags number, matrix, Magic Numbers

Problem 896. Sophie Germain prime

Created by: Aurelien Queffurust

Tags prime, primes, sophie germain

397

Problem 44836. Iccanobif numbers 1

Created by: James

Tags fibonacci, iccanobif

Problem 2690. Armstrong Number

Created by: VIVEK RUHELA

Tags arithmetic, basic matlab

264

Problem 45250. Be happy

Created by: Asif Newaz

Tags number, happy

Problem 156. Parasitic numbers

Created by: the cyclist

Tags parasitic

256

Problem 44385. Extra safe primes

Created by: Matthew Eicholtz

Tags prime numbers, cody5, safe prime

687

Problem 2733. Evil Number

Created by: Jan Orwat

Tags easy, number theory, oeis

217

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

Created by: Jan Orwat

Tags number theory, a138591

130

Problem 1298. P-smooth numbers

Created by: Richard Zapor

Tags primes, find, mod

Problem 44360. Pentagonal Numbers

Created by: goc3

Tags series, number, sequence

602

Problem 166. Kaprekar numbers

Created by: the cyclist

Tags kaprekar

244

Problem 45194. Cantor counting

Created by: Asif Newaz

Tags cantor, rational number

Problem 1096. Largest Twin Primes

Created by: Des Mc Manus

Tags primes

337

Problem 1804. Fangs of a vampire number

Created by: Andrew Newell

Tags factors, number theory

Problem 165. Woodall number

Created by: the cyclist

Tags woodall number theory

140

Problem 525. Mersenne Primes

Created by: Drew Weymouth

Tags math, prime, integers

379

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

Created by: @bmtran (Bryant Tran)

Tags projecteuler, plus15

Problem 933. Ordinal numbers

Created by: Tim

Tags ordinal, lookup table

143

Problem 45249. Frugal number

Created by: Asif Newaz

Tags number, frugal, economical

Problem 2595. Polite numbers. Politeness.

Created by: Jan Orwat

Tags number theory, oeis

122

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

Created by: James

Tags projecteuler, self-referential, golomb sequence

118

Problem 74. Balanced number

Created by: Cody Team

Tags matlab

2105

Problem 249. Project Euler: Problem 9, Pythagorean numbers

Created by: Doug Hull

Tags projecteuler

518

Problem 1742. Generate a Parasitic Number

Created by: James

Tags parasitic, cyclic

Problem 45251. Last non-zero digit

Created by: Asif Newaz

Tags number, factorial

Problem 1925. Smith numbers

Created by: Sky Sartorius

Tags sum, factors

354

Problem 45272. Pseudo-vampire number

Created by: Asif Newaz

Tags numbers, number theory, sequence

Problem 1477. Champernowne Constant

Created by: G K

Tags math

Problem 1825. Find all vampire fangs

Created by: Andrew Newell

Tags factors, number theory

Problem 81. Mandelbrot Numbers

Created by: Cody Team

Tags matlab, fractals

852

Problem 235. Project Euler: Problem 4, Palindromic numbers

Created by: Doug Hull

Tags projecteuler

474

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

Created by: James

Tags primes, projecteuler, circular reasoning

254

1 – 35 of 35

Trial software

Difficulty Rating

Problem Groups

Problems

Problem 2056. Is this number Munchhausen Narcissistic?

Problem 45253. Pell numbers

Problem 45229. Bell Triangle

Problem 896. Sophie Germain prime

Problem 44836. Iccanobif numbers 1

Problem 2690. Armstrong Number

Problem 45250. Be happy

Problem 156. Parasitic numbers

Problem 44385. Extra safe primes

Problem 2733. Evil Number

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

Problem 1298. P-smooth numbers

Problem 44360. Pentagonal Numbers

Problem 166. Kaprekar numbers

Problem 45194. Cantor counting

Problem 1096. Largest Twin Primes

Problem 1804. Fangs of a vampire number

Problem 165. Woodall number

Problem 525. Mersenne Primes

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

Problem 933. Ordinal numbers

Problem 45249. Frugal number

Problem 2595. Polite numbers. Politeness.

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

Problem 74. Balanced number

Problem 249. Project Euler: Problem 9, Pythagorean numbers

Problem 1742. Generate a Parasitic Number

Problem 45251. Last non-zero digit

Problem 1925. Smith numbers

Problem 45272. Pseudo-vampire number

Problem 1477. Champernowne Constant

Problem 1825. Find all vampire fangs

Problem 81. Mandelbrot Numbers

Problem 235. Project Euler: Problem 4, Palindromic numbers

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