Fun maths

In the late 1950s, Selmer M. Johnson and Hale F. Trotter independently created an algorithm – aptly named the Steinhauss-Johnson-Trotter algorithm – which generates all permutations of nn unique objects. Crucially, to get from one permutation to the next, only one next-door-neighbour pair of elements can be swapped, and no permutation can be repeated. Such… Read more

On Christmas day we sat round the table, crossed our arms, and pulled crackers on each side. In mine, I found a silver paper hat, a terrible joke, and a sparkly orange bobble (that I will be keeping). My sister had won the real jackpot; nestled inside her cracker was the magic of modern computing. … Read more