Amicable.lean`

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Project sources: Pinned project documentation, Formal Conjectures paper, arXiv v1

1 declarations, 0 contain sorry, 0 declared as axioms

Amicable numbers

Two natural numbers $a$ and $b$ are amicable if $\sigma(a) = \sigma(b) = a + b$, where $\sigma$ is the sum-of-divisors function.

Imports (1)

Mathlib.NumberTheory.ArithmeticFunction.Misc

Imported by 1 file

FormalConjecturesForMathlib.lean

structure IsAmicable We say that $a,b\in \mathbb{N}$ are an amicable pair if $\sigma(a)=\sigma(b)=a+b$ line 35 source
Source documentation
We say that $a,b\in \mathbb{N}$ are an amicable pair if $\sigma(a)=\sigma(b)=a+b$.

standard axioms: Classical.choice, Quot.sound, propext what this means
Statement uses: Nat
```
structure IsAmicable (a b : ℕ) : Prop where
…
```