E057: Erdős–Kac in practice

Preview figure for E057

Tags: number-theory, quantitative-exploration, visualization, arithmetic-functions, omega, heuristics See: Valid Tags.

Highlights

  • Compute \(\Omega(n)\) for \(n\le N\) and plot its histogram.

  • Optionally normalize to compare with a Gaussian curve (Erdős–Kac heuristic).

Goal

Visualize the probabilistic number-theory flavor of prime-factor counts.

Background (quick refresher)

Research question

How close does the distribution of \(\Omega(n)\) (after normalization) look to a normal curve for moderate \(N\)?

Method

  • Compute \(\Omega(n)\) using an SPF sieve.

  • Plot histogram; optionally overlay a normal density with matching mean/variance approximations.

How to run

  • make run EXP=e057

  • uv run python -m mathxlab.experiments.e057

Outputs

This experiment follows the standard output contract:

  • out/e057/figures/ — generated figures (PNG)

  • out/e057/report.md — short narrative report

  • out/e057/manifest.json — snapshot metadata for the gallery

Published run snapshot

If this experiment is included in the docs gallery, include the published snapshot (report + params).

  • n_max: 400000

  • bins: 60

Figure:

  • fig_01_erdos_kac_hist.png

params.json (snapshot)
{
  "bins": 60,
  "n_max": 400000
}

References

See Erdős and Kac [1940], Tenenbaum [2015].