Triangular and Trapezoidal Numbers
Triangular numbers and trapezoidal numbers are both natural numbers that can be expressed as the sum of more than one consecutive natural numbers.
Sum of Squares
Some numbers can be expressed as the sum of two perfect squares...
Connected Lights
Lights connected in a string or a loop, each attached to a switch that will change the state of the light itself and its neighbours when pressed.
Splitting LCM
Four problems about splitting a natural number into smaller natural numbers.