# Problems

1 – 50 of 172
 Problem Title Likes Solvers Difficulty

#### Problem 57869. Identify de Polignac numbers

Created by: ChrisR

2

5

#### Problem 2738. Sideways sum

Created by: Jan Orwat

1

69

#### Problem 46305. find the value

Created by: Maryam HCTRAK Alhebsi

1

82

#### Problem 46000. Compute the harmonic numbers

Created by: ChrisR

4

59

#### Problem 47803. Check if the input is a strong prime

Created by: Mehmet OZC

1

21

#### Problem 43130. Nth root

Created by: Abhishek Jain

2

115

#### Problem 46054. Count trailing zeros in a primorial

Created by: ChrisR

4

24

#### Problem 45189. Double Factorial

Created by: Mehmet OZC

2

56

2

68

#### Problem 46639. Transform a Decimal number into a Septimal number

Created by: Syed Shahed

1

25

#### Problem 42865. Find the sum of n squares

Created by: William Mitchell

2

184

#### Problem 2369. Tribute to Ramanujan

Created by: rifat

1

29

#### Problem 54370. Determine whether the given number is palindrome or not.

Created by: Abdullah Al Baki

3

24

#### Problem 44748. Amicable numbers

Created by: cdeliu

1

56

#### Problem 45960. Set the Euler-Mascheroni constant with an identity using available MATLAB functions

Created by: ChrisR

1

12

#### Problem 52060. Identify Ruth-Aaron numbers

Created by: ChrisR

3

20

#### Problem 2370. Fermat's last theorem - again

Created by: rifat

1

35

#### Problem 51570. Count numbers whose reciprocals' decimal expansions terminate

Created by: ChrisR

5

12

#### Problem 45224. Wythoff Sequence

Created by: Asif Newaz

2

28

#### Problem 52921. Easy Sequences 40: Quadratic Congruence

Created by: Ramon Villamangca

2

10

#### Problem 49738. Determine whether a prime is Pythagorean

Created by: ChrisR

1

17

#### Problem 47798. Check if the input is a balanced prime

Created by: Mehmet OZC

2

26

#### Problem 52594. Easy Sequences 10: Sum of Cumsums of Fibonacci Sequence

Created by: Ramon Villamangca

2

26

#### Problem 47808. Check if the input is an interprime

Created by: Mehmet OZC

1

20

#### Problem 46016. Determine digits of the Copeland-Erdos constant

Created by: ChrisR

3

15

#### Problem 44230. I'm going to enjoy watching you calculate, Mr Anderson

Created by: James

2

37

#### Problem 50182. Compute the Euler totient function

Created by: ChrisR

1

9

#### Problem 51798. Label primes with the Erdos-Selfridge classification

Created by: ChrisR

1

9

6

643

#### Problem 44229. How brilliant are you?

Created by: James

3

47

#### Problem 1771. Polygonal numbers

Created by: Jan Orwat

5

119

#### Problem 46060. Identify primorial primes

Created by: ChrisR

1

14

#### Problem 54755. List odd twin composites

Created by: ChrisR

1

5

Created by: HH

1

5

#### Problem 2733. Evil Number

Created by: Jan Orwat

3

235

#### Problem 44068. The number of trailing zero digit of a factorial

Created by: Jihye Sofia Seo

3

52

#### Problem 45988. Evaluate the zeta function for real arguments > 1

Created by: ChrisR

2

15

#### Problem 53910. List the dopey numbers

Created by: ChrisR

2

7

#### Problem 56743. Count the unitary divisors of a number

Created by: ChrisR

0

7

#### Problem 51312. Count the square-full divisors of a number

Created by: ChrisR

0

7

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

Created by: Jan Orwat

2

147

#### Problem 44289. Find two triangular numbers whose sum is input.

Created by: Mehmet OZC

2

87

#### Problem 45342. Sieve of Eratosthenes

Created by: Asif Newaz

2

16

#### Problem 45388. Gapful numbers

Created by: Asif Newaz

1

16

#### Problem 46046. Determine whether a number is a cluster prime

Created by: ChrisR

4

15

#### Problem 53880. List the vile numbers

Created by: ChrisR

2

9

#### Problem 44319. Write c^3 as sum of two squares a^2+b^2

Created by: Mehmet OZC

2

310

#### Problem 45964. Compute the nth Pythagorean prime

Created by: ChrisR

1

24

#### Problem 46057. Find the last non-zero digit in a primorial

Created by: ChrisR

1

14

#### Problem 46081. Set Soldner's constant

Created by: ChrisR

1

13

1 – 50 of 172