A maths maestro from Sheffield is preparing to take on some of the best young brains in the US for the chance to win $10,000.
Yuji Okitani, of Tapton School, in Crosspool, fought off competition from 1,100 students to be crowned UK champion of the Who Wants to Be a Mathematician competition in November.
The 17-year-old is now ready to lock minds with winners from the US and Canada when he lines up at the grand final in San Diego next Saturday, January 13.
He and the other 11 finalists will tackle a series of devilishly difficult questions in their search for glory.
As well as securing international bragging rights for their country, the winner will walk away with $5,000 for themselves and the same sum for their school - around £7,400 in total at today's exchange rates.
Yuji said: "I'm quite anxious as they're all going to be very good mathematicians, but I'm looking forward to the trip.
"I never expected to win the UK final. I just thought I would go somewhere and watch someone else win because I've never won anything before."
TAKE OUR QUIZ: Can you solve puzzles Yuji answered to claim UK maths crown?
The teenage board game enthusiast says his gift for maths runs in the family, with his father Koji being a professor at Sheffield University and his twin brother and younger brother both being good with numbers.
Yuji, who has been preparing by watching videos of past finals, is due to fly to San Diego with his dad on Thursday and return the following Tuesday.
Many thousands of students across the US and Canada take part each year in the competition, which is open to anyone aged under 18, but this is the first year the UK winner will be flown across the Atlantic to compete in the grand final.
The UK version of the event was organised by the Good Thinking Society, a charity dedicated to the promotion of science, and was supported by the Department of Mathematical Sciences at the University of Southampton.
Yuji saw off finalists from Surrey, Birmingham and London in the UK finals held at King’s College London Mathematics School on November 24 last year.
Simon Singh, the popular science author who chairs the Good Thinking Society, praised Yuji for claiming the UK title and wished him luck in the grand final.