Proof that "e" is irrational in 1 Tweet:

If e was rational e=p/v= ∑ᵛᵢ₌₀ 1/i! + ∑ᵢ₌ᵥ₊₁ 1/i!
Multiplying by v!

p(v-1)! – ∑ᵛᵢ₌₀ v!/i! = 1/(v+1)+1/(v+1)(v+2)+… <1/(v+1)+1/(v+1)²+…=1/v

The left side is an integer but 0< 1/v <1, hence the assumption is false▪

— Fermat's Library (@fermatslibrary) October 30, 2020