The Collatz conjecture

The Collatz conjecture

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Lesson details

Key learning points

  1. In this lesson, we will learn about a famous unsolved maths problem called The Collatz conjecture.

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5 Questions

Q1.
Fill the gap: Every even integer greater than two can be written as the sum of two __________ integers.
perfect
Correct answer: prime
small
troublesome
Q2.
Goldbach wrote his conjecture in a letter. Who was the letter to?
His parent
His wife
Correct answer: Leonhard Euler
Lohar Collatz
Q3.
What was Mr Golbach's first name?
Antoni
Correct answer: Christian
Lohar
Xavier
Q4.
True or false: Goldbach's conjecture is proven to be true.
Correct answer: False
True
Q5.
Write 7 as a sum of two prime numbers.
2 + 2 + 3
4 + 3
Correct answer: 5 + 2
6 + 1

6 Questions

A sequence is defined as follows: Start with any positive integer value (𝑛). Each term is found from the previous term as follows: If the value is even, divide it by 2 (𝑛/2). If the value is odd, multiply it by 3 and add 1 (3𝑛+1).
Q2.
If the first term of the sequence is 30, what would the second term be?
100
Correct answer: 15
60
91
Q3.
If the second term of the sequence is 30, what would could the first term be?
100
15
Correct answer: 60
91
Q4.
Fill in the gap: The Collatz conjecture states: no matter the start number (𝑛), the sequence will always reach __________.
half of the start number
infinity
Correct answer: one
zero
Q5.
What is the first name of Mr Collatz?
Bob
Christian
Leonard
Correct answer: Lothar
Q6.
In what year did Collatz make his conjecture?
1927
Correct answer: 1937
1997
2007

Lesson appears in

UnitMaths / Famous maths problems