Liouville Function Calculator

λ(n) = (−1)^Ω(n)

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About Liouville Function Calculator

A Liouville function calculator computing λ(n) = (−1)^Ω(n) where Ω(n) is the number of prime factors of n counted WITH multiplicity. λ is completely multiplicative. Its summatory function L(n) = Σλ(k) relates to the Riemann hypothesis. Client-side.

Liouville Function Calculator Features

  • λ(n) value
  • Ω(n) count
  • Summatory L(n)
  • RH connection
  • Sequence
Liouville function: λ(n) = (−1)^Ω(n). λ(1)=1, λ(2)=−1, λ(3)=−1, λ(4)=1 (Ω(4)=2), λ(6)=1 (Ω(6)=2). Completely multiplicative: λ(ab)=λ(a)λ(b) always. The Pólya conjecture (L(n)≤0 for n≥2) is FALSE — first counterexample at n=906,150,257.

How to Use

Enter n:

  • λ(n): +1 or −1
  • Ω(n): Prime factor count
  • L(n): Summatory function

Pólya Conjecture

Pólya (1919) conjectured L(n)=Σλ(k)≤0 for all n≥2. Seemed true for small n. Haselgrove (1958) disproved it. First explicit counterexample: n=906,150,257 where L(n)=1. But L(n) is mostly negative.

Riemann Hypothesis

RH is equivalent to: L(n) = O(n^{1/2+ε}) for every ε>0. If λ-sums grow slower than √n, RH is true. This connects a simple ±1 function to the deepest unsolved problem in mathematics.

Step-by-Step Instructions

  1. 1Enter n.
  2. 2Factor n.
  3. 3Count Ω(n).
  4. 4Compute λ(n).
  5. 5Check L(n).

Liouville Function Calculator — Frequently Asked Questions

How does λ differ from μ (Möbius)?+

μ(n)=0 for non-squarefree n; λ(n) is never 0. μ is multiplicative; λ is COMPLETELY multiplicative (λ(ab)=λ(a)λ(b) always, even when gcd(a,b)>1). The key relationship: Σ_{d|n} λ(d) = 1 if n is a perfect square, 0 otherwise.

What's Ω(n) exactly?+

Ω(n) counts prime factors WITH multiplicity. Ω(12) = Ω(2²·3) = 3 (two 2s + one 3). Compare to ω(n) which counts DISTINCT primes: ω(12)=2. λ uses Ω, not ω.

Why was Pólya's conjecture interesting?+

If true, it would have implied the Riemann Hypothesis! The fact that it's false doesn't disprove RH, but it shows that the 'excess of even-Ω numbers' is not as strong as hoped. The conjecture fails at n ≈ 9×10^8.

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