# Problems

101 – 150 of 167
 Problem Title Likes Solvers Difficulty

#### Problem 53990. Classify product/digit-sum sequences

Created by: ChrisR

4

8

#### Problem 54740. Count the ways to make Scorigami

Created by: ChrisR

1

2

#### Problem 55335. Generate Bernoulli polynomials

Created by: ChrisR

0

5

#### Problem 51565. Convert a number from base 10 to factorial notation

Created by: ChrisR

4

6

#### Problem 56220. Easy Sequences 75: Easy as Pisano Pi

Created by: Ramon Villamangca

1

7

#### Problem 56250. Counting Permutations

Created by: Dyuman Joshi

1

6

#### Problem 56418. Easy Sequences 78: Trailing Zeros of Factorial Numbers at any Base

Created by: Ramon Villamangca

1

3

#### Problem 57298. Easy Sequences 82: Digits of Powers of 2

Created by: Ramon Villamangca

0

3

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

Created by: Ramon Villamangca

0

3

#### Problem 52609. Easy Sequences 11: Factorial Digits without Trailing Zeros

Created by: Ramon Villamangca

1

11

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

Created by: ChrisR

3

9

#### Problem 52866. Easy Sequences 36: Hyperbolic Lattice Points

Created by: Ramon Villamangca

0

7

#### Problem 52724. Easy Sequences 20: Counting Prime-sided Rectangles

Created by: Ramon Villamangca

Tags easy, geometry, area

2

5

#### Problem 53810. List the Beatriz numbers

Created by: ChrisR

3

5

#### Problem 56423. French Conundrum

Created by: Dyuman Joshi

1

5

#### Problem 45272. Pseudo-vampire number

Created by: Asif Newaz

2

18

#### Problem 54720. Hyperperfect Numbers

Created by: Dyuman Joshi

1

4

#### Problem 55370. Easy Sequences 69: Radix Economy of Factorials

Created by: Ramon Villamangca

1

4

#### Problem 1826. Find vampire numbers

Created by: Andrew Newell

11

282

#### Problem 45997. Evaluate the zeta function for complex arguments

Created by: ChrisR

1

9

#### Problem 52764. Easy Sequences 24: Number of Coprime Lattice Points

Created by: Ramon Villamangca

1

6

#### Problem 53119. Easy Sequences 53: Greatest Proper Divisor

Created by: Ramon Villamangca

3

3

Created by: Dyuman Joshi

0

3

#### Problem 52819. Easy Sequences 30: Nearly Pythagorean Triangles

Created by: Ramon Villamangca

2

19

#### Problem 52709. Easy Sequences 19: Length of Prime-sided Rectangle with Maximum Area

Created by: Ramon Villamangca

Tags easy, geometry, area

2

7

#### Problem 52614. Easy Sequences 12: 50th Prime

Created by: Ramon Villamangca

0

11

#### Problem 52634. Easy Sequences 14: Consecutive Composites

Created by: Ramon Villamangca

1

4

#### Problem 52990. Easy Sequences 46: Semi-prime Leap Year Pairs

Created by: Ramon Villamangca

0

2

#### Problem 53009. Easy Sequences 48: Prime Big Omega of Factorial Sequence

Created by: Ramon Villamangca

1

4

#### Problem 53079. Easy Sequences 50: Blocked Gaussian Integers

Created by: Ramon Villamangca

1

2

#### Problem 53955. Determine Fundamental Solution of Pell Equation

Created by: David Hill

1

2

#### Problem 51580. Construct a continued fraction for a square root

Created by: ChrisR

3

8

#### Problem 56458. Easy Sequences 80: Sum of the n-th Row of Fibonacci Square Triangle

Created by: Ramon Villamangca

0

2

#### Problem 42834. Integer complexity (Large numbers)

Created by: Peng Liu

2

17

#### Problem 45274. Fangs of pseudo-vampire number

Created by: Asif Newaz

1

17

#### Problem 52769. Easy Sequences 22: Sum of Proper Fractions

Created by: Ramon Villamangca

1

7

#### Problem 52729. Easy Sequences 21: Combinatorial Summations

Created by: Ramon Villamangca

2

6

#### Problem 52859. Easy Sequences 35: Cutting a donut to Semi-prime pieces

Created by: Ramon Villamangca

0

6

#### Problem 52861. Easy Sequences 37: Natural Factorable Polynomials

Created by: Ramon Villamangca

2

6

#### Problem 54800. Consecutive Pairs of Smooth Numbers from Set of Prime Numbers

Created by: David Hill

0

3

#### Problem 56553. Easy Sequences 81: Fibonacci Radicals

Created by: Ramon Villamangca

1

3

#### Problem 57487. Compute the largest number with a given integer complexity

Created by: ChrisR

2

4

#### Problem 52684. Easy Sequences 17: Mu Variant Function

Created by: Ramon Villamangca

1

4

#### Problem 52659. Easy Sequences 15: Pythagorean Area with maximum Hypotenuse

Created by: Ramon Villamangca

1

7

#### Problem 2160. The 17x17 Problem

Created by: Ned Gulley

1

7

#### Problem 44788. Find the right number make the equation

Created by: Binbin Qi

2

9

#### Problem 52834. Easy Sequences 32: Almost Pythagorean Triples

Created by: Ramon Villamangca

2

4

#### Problem 53125. Easy Sequences 54: Product of Products of Proper Divisors

Created by: Ramon Villamangca

1

2

#### Problem 53730. Easy Sequences 57: "Pretty-gorean" Triangles?

Created by: Ramon Villamangca

0

3

#### Problem 53740. Easy Sequences 59: Almost Twin Primes

Created by: Ramon Villamangca

1

2

101 – 150 of 167