Along with three other mathematicians, he created a formula for devising tie knots using just three symbols, W, T and U.

He said: ‘T is a clockwise (turnwise) move of the knot-tying blade, W is a counter-clockwise move, and U tucks the blade under a previous bow.

‘Whether to start with an inwards or outwards crossing can be deduced by counting the total number of W and T in the knot description string, and all possible strings in W and T produce possible tie knots.’