86,000+ olympiad problems in six free banks 🧮⚛️🧪💻🧬🔭
Maths, physics, chemistry, informatics, biology and astronomy, in English with LaTeX.
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https://t.co/OlLggGUM2W
The strings fall silent; their hands meet.
In Max Volkhart’s “The End of the Song,” the conversation seems to be just beginning.
#ArtHistory#Painting#eisatopon
https://t.co/8tL20CpCma
🔢 A remarkable theorem from 1862!
For every prime p ≥ 5, the numerator of
1 + 1/2 + ··· + 1/(p−1)
is divisible by p².
The hidden power of primes!
#eisatopon#NumberTheory#Mathematics
https://t.co/TvSaWd46Z1
🐘 More than a touching moment.
Animals deserve not only our kindness, but our respect, protection, and the freedom to live with dignity.
The way we treat them says much about our humanity.
#eisatopon#AnimalWelfare#RespectForLife
https://t.co/vBeQdIOHrs
🎯 Two players start at 0 and take turns adding a number from 1 to 9.
The first to reach a three-digit number wins.
Who has a guaranteed winning strategy?
#eisatopon#MathPuzzle#GameTheory
https://t.co/yBGagG76Sm
🔢 72 and 99 give 27.
27 and 45 give 18.
The pattern continues… but the final 7 is NOT a mistake!
Can you find x?
#eisatopon#MathPuzzle#BrainTeaser
https://t.co/A7PmSEfLYr
🔢 A prime with 6,400 digits: 6,399 nines and just ONE eight!
Harvey Dubner discovered it in 1991.
10⁶⁴⁰⁰ − 10⁶³⁵² − 1
#eisatopon#PrimeNumbers#NumberTheory
https://t.co/BmP6wtNVa5
♟️ One grain of rice on the first chessboard square. Double it on each next square.
Total: 18,446,744,073,709,551,615 grains!
The final square alone has ONE grain more than the previous 63 combined.
#eisatopon#Mathematics#ExponentialGrowth
https://t.co/dcn46M6d0Q
📐 Five regular pentagons. Four are congruent.
Can you find the area ratio of one small pentagon to the large one?
#eisatopon#Geometry#MathChallenge
https://t.co/tojAky7aIL
🔢 The Basel Problem puzzled mathematicians for 90 years!
In 1734, Euler discovered:
1 + 1/4 + 1/9 + 1/16 + ··· = π²/6
An astonishing connection between infinity and π!
#eisatopon#MathHistory#Mathematics
https://t.co/Hh8GtdzqGH
🔢 8 = 2³ and 9 = 3².
They are the ONLY consecutive perfect powers greater than 1!
Conjectured by Catalan in 1844, proved by Mihăilescu in 2002.
#eisatopon#NumberTheory#Mathematics
https://t.co/3qyA6etTf9
🌕How large are the major moons of Jupiter and Saturn?
A beautiful size comparison with Earth as reference shows just how impressive Ganymede, Titan, Callisto and the others really are.
#eisatopon#Astronomy#SpaceScience
https://t.co/ef41AsQGog
📄 Why is A4 paper exactly 210 × 297 mm?
The secret is √2!
Halve an A-series sheet, and the new rectangle keeps the same proportions.
A beautiful piece of mathematics hiding in everyday life!
#eisatopon#Geometry#Mathematics
https://t.co/rSuVIsdy15
🔢 Is it a coincidence that PRIME adds up to a prime?
P=16, R=18, I=9, M=13, E=5
16+18+9+13+5 = 61
And 61 is prime!
#eisatopon#PrimeNumbers#MathFun
https://t.co/RCIRPqLYWu
🎲 Kiyosi Itô died on November 10, 2008.
His stochastic calculus revealed a remarkable rule:
d(Bₜ²) = 2Bₜ dBₜ + dt
That extra dt changed how we model randomness.
#eisatopon#Mathematics#Probability
https://t.co/3df9VDr5ko
🌐 You can't comb a hairy sphere perfectly flat!
Every continuous tangent vector field on a sphere must vanish somewhere.
But on a torus? No zero is required.
Topology makes the difference!
#eisatopon#Topology#Mathematics
https://t.co/ylk6d3l7AR
🌀 A surface can curve everywhere and still have zero mean curvature!
Enneper's surface (1864) even intersects itself as it extends.
Minimal does NOT mean flat.
#eisatopon#Geometry#Mathematics
https://t.co/ftq79Y9t3e
📚 During a job interview, Olga Taussky was asked an inappropriate question about her joint research papers.
G. H. Hardy interrupted:
"That is a most improper question. Do not answer it!"
#eisatopon#MathHistory#WomenInMath
https://t.co/EU9uyh2Yem
🔢 Mathematics once had a 16-letter word for x⁸:
ZENZIZENZIZENZIC!
Robert Recorde used the 17-letter spelling "zenzizenzizenzike" in 1557.
#eisatopon#MathHistory#Mathematics