🇫🇷 Alexis Lemaire

Alexis Lemaire was born in 1980 in France. Unlike many calculation prodigies, his story is not one of a circus-stage childhood; he was an academic, and his interest in mental arithmetic ran in parallel with a formal scientific career. He would go on to earn a PhD in computer science, focused on artificial intelligence, from the University of Reims — and the connection between those two pursuits is, by his own account, the whole point.

He specialised in a single, brutally specific discipline: the integer thirteenth root of very large numbers. The thirteenth root is chosen by calculators because of a quirk of arithmetic that makes the last digits of the answer relatively tractable while the rest is anything but. Lemaire built his reputation first on 100-digit numbers and then on the far harder 200-digit problem.

His progress reads like a series of demolitions of his own records. On 10 May 2002 he calculated the thirteenth root of a 100-digit number in 13.55 seconds, beating a long-standing mark held by the Dutch calculator Willem Klein. On 17 December 2004 he cut that to 3.625 seconds — the time, again, including reading the question and speaking the answer. Then he turned to 200 digits.

The 200-digit problem was a different order of difficulty. His first success, on 6 April 2005, took 8 minutes 33 seconds. By 30 July 2007, at the Museum of the History of Science in Oxford, he had it down to 77.99 seconds. And on 15 November 2007, at the Science Museum in London, he reached 70.2 seconds — the performance that made headlines around the world and put 'mathlete' into the dictionary of public usage.

Lemaire has always been guarded about his method, and deliberately so. "I will not say exactly what is my method," he told reporters. "I am doing something like artificial intelligence in reverse, because I am imitating a computer." That phrase — artificial intelligence in reverse — is the key to him. His doctoral research was in AI; his calculating was, in effect, the same problem run the other way, a human deliberately implementing the kinds of pattern-recognition and look-up strategies a machine would use.

This made him a slightly different figure from the traditional savant or stage calculator. He was not claiming a mysterious gift. He was a computer scientist treating his own brain as a piece of hardware to be programmed, and his records were as much a demonstration of method as of raw talent. He has spoken of memorising vast quantities of intermediate results so that the calculation becomes, in large part, fast retrieval.

The word he gave the language captures something real about him. A 'mathlete' is not a wizard; it is an athlete — someone who trains a specific capacity to a competitive peak. Lemaire's thirteenth-root records were the product of relentless, narrow, disciplined practice, the arithmetical equivalent of a sprinter shaving hundredths of a second off a time.

Alexis Lemaire's combination of feats and framing left a particular mark on the mental-calculation world. He showed that the spectacular end of human arithmetic could be approached not as magic but as engineering — that you could study how computers solve a problem and then teach yourself, painstakingly, to be one.