This story is from Extraordinary Senses: The attack that made me a maths genius, an episode of Outlook presented and produced by Saskia Edwards. To listen to more episodes of Outlook from the BBC World Service, please click here. "I don't know why I like perfect squares," he says. "It's not just a perfect square, it's two to the power of four or four squared but I just like perfect squares…I automatically do that stuff with everything."