The Sunroom’s Arithmetic

When my sister and I first saw the farmhouse on the edge of the Kansas flatlands, we knew it was special. The realtor called it a ‘fixer-upper,’ but to us it was a blank canvas, a chance to start fresh after Dad’s passing. The house had stood empty for decades, its white clapboard faded to a weary gray, and the wraparound porch sagged like a tired old man. But inside, the bones were good, the hardwood floors solid, the high ceilings full of promise. The only oddity was a small sunroom jutting off the back, with walls covered in peculiar, hand-painted numbers—not graffiti, but neat, precise figures in a strange sequence: 3, 7, 13, 21, 31… They ran along the baseboards, climbed the doorframes, and circled the frosted glass panes.

We threw ourselves into renovation, my sister Lila and I, armed with paint scrapers and determination. Lila was the organized one, meticulously cataloging each family heirloom we found forgotten in attic trunks: sepia photographs of stern-faced ancestors, a child’s porcelain doll with a cracked face, a bundle of yellowed letters tied with ribbon. I focused on the physical labor, sanding floors, patching plaster. The numbers in the sunroom, though, resisted every attempt to paint over them. The paint would dry, then bubble and peel, revealing the figures as vivid as if freshly inked. Lila, ever the pragmatist, suggested we just cover the walls with paneling, but I felt a strange reluctance to hide them. They seemed intentional, like a code waiting to be broken.

One evening, after a long day of work, Lila was reading one of the letters aloud by the fireplace in the living room. It was dated 1945, from a woman named Esther to her brother, James. She wrote about the routine of farm life, the price of wheat, and her concern for her son, Thomas, who had recently taken to ‘counting the seams in the walls.’ Lila laughed, ‘Kids have such wild imaginations.’ But a cold knot tightened in my stomach. I looked up ‘Thomas Kingsley’ in the county records we had found in a desk drawer. There was a death certificate: Thomas Kingsley, age 7, died of ‘unknown causes’ in that very house, in 1946.

That night, I couldn’t sleep. I kept thinking about the numbers. They started at 3 and increased by 4, then 6, then 8—as if each increment was double the margin of error. I got out a notebook and started to calculate, half-joking, what the next number would be. If the pattern continued, the next discrepancy would be 43, then 57, then 73. In the dead silence, I watched my pencil move, and when I looked up from the page, the sunroom door was slightly ajar. I hadn’t left it open. The house seemed to hold its breath.

The next day, we had a contractor over to look at the foundation. As he walked through the sunroom, he paused, running his finger over a cluster of numbers above the window. ‘Odd,’ he said, ‘these aren’t random. They’re prime numbers only: 3, 7, 13, 31, 43, 73… but some are missing.’ He pointed out that primes are numbers divisible only by 1 and themselves. My blood ran cold. I had been so focused on the differences that I hadn’t noticed they were all primes. And the missing ones—5, 11, 17—were absent. The sequence was deliberately skewed.

We decided to spend the night to see if we could capture any strange noises on our phones’ voice recorders, thinking maybe the original residents had hidden something. We placed a recorder in the sunroom and one in the hallway. Around 3:00 AM, we were jolted awake by a thunderous crash from the sunroom. We rushed in to find every window had shattered inward, and on the wall, now fully exposed, was a final number painted in a deep, dried-blood red: 0. The only thing left intact was Esther’s photograph, which had somehow teleported from the box in the attic to the mantelpiece, face turned to the wall.

Terrified, we called a local historian, a retired professor named Dr. Amelia Brooks. She examined the house and, with a grave face, told us about a phenomenon she called ‘numerical hauntings.’ ‘These numbers are a mathematical exorcism,’ she explained. ‘The original owner, a recluse mathematician named Arthur Hemmings, believed that negative primes—like -2, -3—were gateways. He used the sequence of positive primes to create a lock, but his son, Thomas, who was born with a gift for seeing these things, realized the lock was flawed: it was missing the negative primes. He tried to correct it, but his father, in a fit of madness, sealed the error in the sunroom.’ She showed us an old ledger with the formula: the house was a fulcrum, and the missing negative primes would someday ‘clamp shut’ the rift, but until then, entities could slip through.

Lila and I spent the next week frantically trying to find the negative primes. We painted the numbers -2, -3, -5, -7, -11, -13, -17 on the walls, but they would always fade or smudge. We tried using iodine, chalk, even charcoal, but nothing stuck. The number 0 remained, a glaring void, and the house grew colder day by day. We started hearing whispers in the static of our recorders, and I saw a silhouette of a small boy standing in the sunroom doorway, pointing at the 0, his mouth open in a silent scream.

One night, I woke to find Lila standing at the window of our bedroom, her back to me, repeating a string of numbers in a monotone: ‘-2, -5, -11, -17…’ She turned, and her eyes were milky white. ‘He’s counting the rest,’ she whispered, and then she collapsed. The next morning, she had no memory of the event, but she found her notebook filled with calculations, all leading to a single number: -197, the last missing negative prime. We knew what we had to do, but I was terrified.

We ordered a custom stencil and a can of phosphorescent paint. That night, under the light of a waning moon, we traced the negative primes across the sunroom walls in a spiraling pattern, ending with -197 directly beneath the 0. As we painted the final digit, the air in the room crystallized. The numbers glowed a faint, otherworldly blue, and then they began to shift, rearranging themselves into a single equation: 0 = (-2) + (-3) + (-5) + … The room went silent, and the next day, when the sun rose, we found the sunroom walls blank, the numbers gone. But in the center of the floor, there was a small, child’s handprint pressed into the dust, as if Thomas had finally found his answer.

We stayed long enough to renovate the house, but we never slept in the sunroom again. We eventually sold it to a young couple expecting their first child, warning them about the peculiar smell of old paper that sometimes emanated from the walls. Now, I teach mathematics at a community college, and every time I see the number 0, I feel a chill. And sometimes, late at night, I can hear my brother’s voice on the other side of a door that doesn’t exist, counting, counting, counting… but he always stops before he reaches zero.