Chapter 14
Chapter 14
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Translator: Ace
Chapter: 14
Chapter Title: Korean Mathematical Olympiad Preliminary
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Monday.
Yoo Seo-ha woke up earlier than usual.
The dawn air seeping through the window felt chilly. Mid-November already—winter was right around the corner.
Today was the first preliminary round of the Korean Mathematical Olympiad.
Seo-ha sat up in bed and opened the window. Cool air filled his lungs deeply, chasing away any remnants of sleep.
He changed into light workout clothes and quietly slipped out the door.
It was 6 a.m. The village was still silent, but he could sense people here and there starting their day. Seo-ha began jogging at an easy pace.
There was a reason he'd started running.
The mathematician Ramanujan had died at 32 from malnutrition and tuberculosis.
The cause? An extremely irregular lifestyle and lack of exercise. He'd spent every day sitting for hours, lost in mathematical research.
History of Mathematicians had been a fascinating read for Seo-ha.
Tracing the development of math from East to West, peeking into the lives of great minds—it was pure joy.
Like how Gauss had summed the numbers from 1 to 100 in seconds at age seven, or how Euler kept researching even after losing his sight. Or the absurd tale of Galois obsessing over his group theory proofs right before a duel.
They'd all been kids once, just like him. They'd all fallen for math's allure at some point, felt frustration and ecstasy by turns. It was amazing to think about.
Sometimes, Seo-ha even felt like he was transcending time and space, conversing with them, breathing the same air.
'Ramanujan could have lived longer...'
The loss to mathematics from his death was incalculable.
In his short 32 years, he'd left behind over 3,900 formulas and theorems. Many weren't proven true until 60 years after his death, at the end of the 20th century.
Only after computers advanced did the world confirm how precise his intuition had been.
'What if he'd lived to 70?'
Even in that brief life, his work on infinite series and continued fractions became the foundation of modern cryptography and computer science. And the theta function from his final letter? It's key to determining dimensions in superstring theory and M-theory, the biggest enigmas in modern physics.
But what was truly unbearable was how much of his theta function remained unsolved even now.
'What a terrible personality.'
Why did mathematicians toss out these crucial problems without proofs and just leave?
Seo-ha couldn't understand it.
How could they so boldly release unfinished ideas to the world?
Ramanujan especially—most of his results skipped proofs entirely, claiming the goddess Namagiri whispered them in his dreams. And yet, they were almost always right. It drove Seo-ha mad.
The history he'd read was a battle against poor health.
So he ran.
Whoosh, whoosh.
His breath came right up to his chin.
Once he got into it, running had benefits beyond health.
His mind, which automatically counted steps, finally stopped calculating. Ideas bubbled up naturally mid-stride—answers that wouldn't come when he sat agonizing over them.
Six months since he started running.
He used to gasp after less than ten minutes. Now thirty was a breeze.
'Is this endorphins?'
Someone appeared in the distance.
"Seo-ha! Take some cucumbers and tomatoes!"
Mr. Choi, who ran the greenhouse, waved at him.
"Thanks, sir! Mom will love them!"
Seo-ha was already a local celebrity in Okcheon.
After circling the village, he headed home. A pleasant warmth spread through his body, and his mind felt refreshingly clear.
"Come on in! What'd they give you this time? Wash up and eat breakfast!"
Mi-young took the bag from his hands.
After a shower, he sat at the table to a more lavish spread than usual.
'Mom and Dad seem more nervous than I am.'
"Mom, you didn't have to go all out like this..."
"Still, it's a big day. You need a proper meal."
In truth, Mi-young hadn't slept well the night before.
She knew her son was brilliant, but parents worry. She'd dozed fitfully, then gotten up to prep breakfast, ending up with extras.
"Whoa! So much yummy food!"
Seo-eun, who'd been half-asleep from waking early, shrieked and plopped down at the table.
Cheol-ho smiled at her.
"Mom made it special for your brother to ace his exam."
"Then no worries! Big bro knows everything. He answers all my questions. Even Mom and the teachers say they don't know sometimes!"
The family burst into laughter at Seo-eun's words.
In a high school in central Daejeon, plenty of students were already there when Seo-ha arrived at the testing center.
'Wow, so many people.'
This year, over 8,000 students nationwide entered the KMO.
Testing sites spanned the 16 provinces, and Daejeon alone had over 500 kids—split across three school buildings because one wasn't enough. It felt like every math whiz in the country was here.
Only 200 would advance from the first round, earning specs for special admissions or gifted science tracks in college entrance.
Corridors and classrooms buzzed with last-minute prep.
A kid in the front row sat with hands clasped, eyes shut. Another muttered formulas from scribbled notes, repeating them.
It was a tension he'd never felt before.
The proctor entered.
"We will now begin the Korean Mathematical Olympiad first preliminary round. The test is three hours, 25 multiple-choice questions, all true/false or A/B/C/D/E. This selects Korea's representatives, so give it your all—no regrets."
Beeeep—
Question sheets and answer forms were handed out. The test began.
'Any new challenges?'
He'd heard the first round threw in clever problems yearly to spot top talent. Seo-ha's heart raced.
Question 1.
[When tossing four coins at once, what's the probability of exactly two heads?]
A probability problem.
Easy with combinations or binomial theorem. Seo-ha marked the answer without writing steps.
Question 2.
[Painting the four vertices of a square red, blue, or green—how many distinct ways?]
'Haha!'
Coloring problem. The unsolved Four Color Theorem sprang to mind. Seo-ha never forgot unproven problems.
He tested new approaches whenever clues emerged.
'Compared to the Four Color Theorem, this is nothing.'
Burnside's lemma made it simple. Rotation group size 4; fixed colorings per rotation...
His hand flew to the right answer.
Difficulty ramped up as he went.
Question 7 had a sneaky trap for missing conditions, but it didn't faze him. He saw numbers not as fragments, but as group patterns. The overall structure held regardless.
Question 10 was similar—forcing root calculations leading to traps. But Seo-ha viewed it as graph trajectories, not mere roots.
From 11, it was hardcore: complex geometry, analysis limits, graph theory, etc.
'Huh?'
His pen paused mid-problem.
'This is weird.'
1, 4, 2, 5, 3, 2, 5, 3, 1, 4, 3, 1...
He stared at his half-marked answer sheet.
Evenly spread from 1 to 5. A 5x5 grid formed in his mind, marked numbers assigning coordinates and rearranging.
Then he noticed the horizontal and vertical alignments were eerily balanced.
'Orthogonal array?'
No coincidence.
Odds of random even distribution: 1 in 500,000. Factoring orthogonality? Less than 1 in 100 billion.
Someone had deliberately embedded all answers in one combinatorial structure.
Seo-ha set problems aside and tackled the puzzle.
His mental chessboard grid filled. Columns had no repeats. Rows perfectly spanned all five numbers.
'Latin square.'
Hypothesis formed instantly.
Treat problems as grid coordinates (i,j); find coefficients a,b to restore all answers.
'Answer: (a·i + b·j) mod 5 + 1.'
He set down his pen.
25 cells complete. Beautiful order in every row and column.
He knew the next answer: position (3,3).
'4.'
Verification time.
His solving hand sped up.
Spot on: 4.
A grin spread across his face.
It was like an invisible test designer speaking to him.
'See the pattern?'
Perfect scorers on KMO first round? Fewer than 10 a year.
This was the designer's nod to them—a hidden message. Of course, no expectation they'd notice.
But Seo-ha filled it midway through.
14, 15, 16...
No need to solve; answers were right there.
Plug in without calc—always precise.
Up to 24, flawless.
Then 25.
'5?'
Should be 1, but it pointed elsewhere.
His right eyelid twitched.
Grid formula couldn't be wrong. Perfect for 24—only 25?
'Did I miss something?'
He retraced every step mentally. No errors.
Just to check, he gripped his pen and re-solved 25 from scratch.
Polycube.
Combinations with rotations, reflections, symmetries.
Still 5.
Thump, thump.
His breathing grew ragged.
'This isn't a sequence or puzzle. It's a test—you fill in the answer.'
He knew it, but his marking hand trembled.
'Just mark 5 and finish.'
Eyes squeezed shut, he brought the marker to the sheet.
But he couldn't color it.
An imperfect pattern. An unexplained exception.
He couldn't accept ruining the array.
Cold sweat beaded on his forehead.