# Problems

51 – 89 of 89
 Problem Title Likes Solvers Difficulty

#### Problem 241. Project Euler: Problem 7, Nth prime

Created by: Doug Hull

15

1114

#### Problem 2340. Numbers spiral diagonals (Part 1)

Created by: Jean-Marie Sainthillier

3

165

#### Problem 46594. Create a sequence of primes p such that p > n π(p)

Created by: ChrisR

1

9

#### Problem 46099. Identify full reptend primes

Created by: ChrisR

0

10

#### Problem 52669. Count the primes in Collatz sequences

Created by: ChrisR

1

11

#### Problem 47833. List the delete-a-digit primes

Created by: ChrisR

3

16

#### Problem 1697. Make a Pandiagonal Prime Magic Square: 11 x 11

Created by: Richard Zapor

2

12

#### Problem 54700. Leyland Primes

Created by: Dyuman Joshi

1

5

#### Problem 52497. Easy Sequences 3: Prime 44-number Squares

Created by: Ramon Villamangca

1

23

#### Problem 365. Numbers with prime factors 2, 3 and 5.

Created by: elias GR

Tags primes, factors

4

413

#### Problem 42914. Counting the Grand Primes

Created by: John D'Errico

3

40

#### Problem 52789. Easy Sequences 26: Prime-Integer Line Segments

Created by: Ramon Villamangca

1

5

#### Problem 49778. Determine whether a number is a prime self number

Created by: ChrisR

4

11

#### Problem 51241. Compute home primes in a given base

Created by: ChrisR

0

6

#### Problem 47518. Play Outside In with primes

Created by: ChrisR

1

7

#### Problem 46087. Investigate the frequency of last non-zero digits of primorials

Created by: ChrisR

1

8

#### Problem 45994. Investigate the frequency of last digits of prime numbers

Created by: ChrisR

3

12

#### Problem 47895. List the dihedral primes

Created by: ChrisR

2

9

#### Problem 51758. List Proth primes

Created by: ChrisR

Tags primes

1

9

#### Problem 48075. Play PRIMEGAME

Created by: ChrisR

2

10

#### Problem 49783. List the good primes

Created by: ChrisR

Tags primes

1

11

#### Problem 60. The Goldbach Conjecture

Created by: Cody Team

Tags primes

57

4795

#### Problem 64. The Goldbach Conjecture, Part 2

Created by: Cody Team

Tags primes

16

1911

#### Problem 52784. Easy Sequences 38: Prime Number Delta

Created by: Ramon Villamangca

1

4

#### Problem 57477. Solve an equation involving primes and fractions

Created by: ChrisR

2

3

#### Problem 659. How long is the longest prime diagonal?

Created by: Ned Gulley

14

375

#### Problem 46066. Evaluate the logarithmic integral

Created by: ChrisR

1

12

#### Problem 46582. Find jumping medalists

Created by: ChrisR

3

13

#### Problem 46701. Compute the nth Naerogahtyp emirp

Created by: ChrisR

1

10

Created by: CXD

1

6

#### Problem 52183. List the nth prime quartet prefix

Created by: ChrisR

0

6

#### Problem 57417. Easy Sequences 86: The "real" Hyperprimorials

Created by: Ramon Villamangca

0

3

#### Problem 83. Prime factor digits

Created by: Cody Team

Tags primes

20

1748

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

Created by: James

7

293

#### Problem 46050. Construct a prime circle

Created by: ChrisR

Tags primes

6

19

#### Problem 51077. List composite numbers that cannot be written as the sum of two primes

Created by: ChrisR

3

9

#### Problem 53810. List the Beatriz numbers

Created by: ChrisR

3

5

#### Problem 54620. List the Euclid numbers

Created by: ChrisR

0

6

#### Problem 52313. Truncatable Primes

Created by: Dyuman Joshi

Tags primes

2

5

51 – 89 of 89