Divisible Factorisationslive
Age 16 to 18
Challenge Level
Can you show that $n^5-n^3$ is always divisible by $24$?
Square Remainderslive
Age 16 to 18
Challenge Level
What is the remainder if you divide a square number by $8$?
Proper Factorslive
Age 16 to 18
Challenge Level
Can you find the smallest integer which has exactly 426 proper factors?
Square Differencelive
Age 16 to 18
Challenge Level
Which numbers can you write as a difference of two squares? In how many ways can you write $pq$ as a difference of two squares if $p$ and $q$ are prime?
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NRICH is part of the family of activities in the Millennium Mathematics Project.
NRICH is part of the family of activities in the Millennium Mathematics Project.