Algebra Etc.

Tweets about algebra, number theory, and miscellaneous math by @JohnDCook.

[Algebra Etc. @AlgebraFact]

Why are Noetherian Rings Special? https://t.co/k8KlowRLcm

[Algebra Etc. @AlgebraFact]

Finding where two conic sections intersect https://t.co/Gu61NbVeeV

[Algebra Etc. @AlgebraFact]

The only Fibonacci numbers that are cubes are 1 and 8.

[Algebra Etc. @AlgebraFact]

Random hexagonal fractals

Different ways of defining the center of a triangle lead to different images.

https://t.co/j42ysXH5O5

[Algebra Etc. @AlgebraFact]

(x + y)^p = x^p + y^p in a field of characteristic p.

[Algebra Etc. @AlgebraFact]

“The closer one looks, the more subtle and remarkable Gaussian elimination appears.” — Lloyd Trefethen

[Algebra Etc. @AlgebraFact]

How Lewis Carroll computed determinants https://t.co/n1xDcy4DjJ

[Algebra Etc. @AlgebraFact]

Latest newsletter:

Online algorithms, polynomial identity testing, and a Gaussian approximation

https://t.co/NyHTaDG5d3

[Computer Science @CompSciFact]

Spot checking polynomial identities

https://t.co/nDlxIGEeDH

[Algebra Etc. @AlgebraFact]

Chen’s theorem: There are infinitely many primes p such that p+2 is either prime or the product of two primes.

[Algebra Etc. @AlgebraFact]

The equation a^b = b^a has only one solution for positive integers a > b.

[Algebra Etc. @AlgebraFact]

'The notion of a Kan extension subsumes all the other fundamental concepts of category theory.' -- Saunders MacLane

[Algebra Etc. @AlgebraFact]

Floor exercises https://t.co/pXsc04K2EL

[Algebra Etc. @AlgebraFact]

Exponential sum of the day

[Algebra Etc. @AlgebraFact]

The number of group homomorphisms between integers mod m and integers mod n is gcd(m,n).

[Algebra Etc. @AlgebraFact]

Details on Besace curves and how to fit them, as in the Meta logo.

https://t.co/LukU94zoYQ

[Algebra Etc. @AlgebraFact]

The Meta logo is approximately a Besace curve.

[Algebra Etc. @AlgebraFact]

Typo: there should be a minus sign in front of the second equation.

[Algebra Etc. @AlgebraFact]

Every integer greater than 77 is the sum of integers whose reciprocals sum to 1.