/- Copyright 2025 The Formal Conjectures Authors. Licensed under the Apache License, Version 2.0 (the "License"); you may not use this file except in compliance with the License. You may obtain a copy of the License at https://www.apache.org/licenses/LICENSE-2.0 Unless required by applicable law or agreed to in writing, software distributed under the License is distributed on an "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the License for the specific language governing permissions and limitations under the License. -/ import FormalConjecturesUtil

Normality of mathematical constants

Despite extensive empirical evidence—billions of digits have been computed for $\pi$, $e$, and $\sqrt{2}$, all showing near-uniform digit distribution—it is an open problem whether any of the classical constants $\pi$, $e$, $\sqrt{2}$, $\ln 2$, or $\varphi$ is normal in any base.

References:

open Real namespace NormalNumber

$\pi$ is normal in base 10.

@[category research open, AMS 11] theorem declaration uses 'sorry'pi_normal_base_ten : IsNormalInBase 10 π := IsNormalInBase 10 π All goals completed! 🐙 end NormalNumber