The hyperbola-based characterization of the factorization parameter

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Let nn be the integer under consideration, let yy and zz be integers, and define

f1(ε)=4ε2+4(1−n)ε+n2−6n+1,f_{1}(\varepsilon)=4\varepsilon^2+4(1-n)\varepsilon+n^2-6n+1, f2(ε)=4(n2−2n+1)ε2+4(3n2−n3−3n+1)ε+n4−8n3+14n2−8n+1.f_{2}(\varepsilon)=4(n^2-2n+1)\varepsilon^2+4(3n^2-n^3-3n+1)\varepsilon+n^4-8n^3+14n^2-8n+1.

Define

Γ={i∈Z>0:f1(i)=y2 or f2(i)=z2}.\Gamma=\left\{i\in\mathbb{Z}_{>0}: f_{1}(i)=y^2\text{ or }f_{2}(i)=z^2\right\}.

Hyperbola-based factoring conjecture. The set Γ\Gamma has exactly three elements and satisfies

Γ={ε1,ε2,n},\Gamma=\{\varepsilon_{1},\varepsilon_{2},n\},

with ε1+ε2=n−1\varepsilon_{1}+\varepsilon_{2}=n-1 and

f2(ε1)=f1(n)f1(ε1).f_{2}(\varepsilon_{1})=f_{1}(n)f_{1}(\varepsilon_{1}).

Moreover,

ε=min⁡{ε1,ε2},max⁡Γ=n.\varepsilon=\min\{\varepsilon_{1},\varepsilon_{2}\},\qquad \max \Gamma=n.

This claim is intended to characterize the parameter ε\varepsilon used in the paper's hyperbola-based approach to factoring integers. The supplied text gives no evidence establishing or refuting it, so its status remains open.

References

Primary source

Gilda Rech Bansimba, Regis Freguin Babindamana and Basile Guy R. Bossoto, “A New Hyperbola based Approach to factoring Integers”, arXiv:2304.07474 (2023).

Progress summary

Refreshed
Claimed solved

A reader has posted a purported complete proof for odd semiprime inputs, but it has not been independently verified, so the conjecture is not settled.

Bansimba, Babindamana, and Bossoto introduced this three-point characterization as Conjecture 2.12\mathrm{2.12} in a paper first posted on April 15, 2023. The paper presents it as an unproved assertion within a proposed factoring method.

Posted attempt

A posted argument claims a complete proof for n=pqn=pq with odd primes p,qp,q: it observes that f2(e)=(n−1)2f1(e)f_{2}(e)=(n-1)^{2}f_{1}(e), reduces square values to factor pairs of nn, and obtains exactly the three claimed positive values. The attempt has not been independently verified.

Current status (as of August 2026): A complete proof has been claimed for odd semiprime nn, but the characterization remains unverified; no published proof, counterexample, or independent confirmation was found.

Sources

Solutions 1

ProofThis solution needs a summarySee full solutionHide full solution

Write n=pqn=pq, where p,qp,q are odd primes, and put

f1(e)=4e2+4(1−n)e+n2−6n+1,f_1(e)=4e^2+4(1-n)e+n^2-6n+1, f2(e)=4(n2−2n+1)e2+4(3n2−n3−3n+1)e+n4−8n3+14n2−8n+1.f_2(e) =4(n^2-2n+1)e^2 +4(3n^2-n^3-3n+1)e +n^4-8n^3+14n^2-8n+1.

Direct expansion gives the polynomial identities

f2(e)=(n−1)2f1(e),f1(n)=(n−1)2.f_2(e)=(n-1)^2f_1(e), \qquad f_1(n)=(n-1)^2.

Since n−1≠0n-1\ne0, f2(e)f_2(e) is an integer square if and only if f1(e)f_1(e) is. Indeed, if

(n−1)2f1(e)=z2,(n-1)^2f_1(e)=z^2,

prime valuations imply n−1∣zn-1\mid z, and therefore

f1(e)=(zn−1)2.f_1(e)=\left(\frac{z}{n-1}\right)^2.

Consequently

Γ={e∈Z>0:f1(e) is a square}.\Gamma=\{e\in\mathbb Z_{>0}:f_1(e)\text{ is a square}\}.

Completing the square gives

f1(e)=(2e+1−n)2−4n.f_1(e)=(2e+1-n)^2-4n.

Since nn is odd, any integer yy satisfying f1(e)=y2f_1(e)=y^2 must be even. Put

r=e−n−12,s=y2.r=e-\frac{n-1}{2},\qquad s=\frac y2.

Then

(r−s)(r+s)=n=pq.(r-s)(r+s)=n=pq.

The factors are odd and have the same sign. Up to order, their absolute values are (1,n)(1,n) or (p,q)(p,q). Hence

r∈{n+12,−n+12,p+q2,−p+q2},r\in\left\{ \frac{n+1}{2},-\frac{n+1}{2}, \frac{p+q}{2},-\frac{p+q}{2} \right\},

and therefore

e∈{−1,n−1−p−q2,n−1+p+q2,n}.e\in\left\{ -1,\frac{n-1-p-q}{2}, \frac{n-1+p+q}{2},n \right\}.

Discarding the nonpositive value −1-1, define

ε1=n−1−p−q2,ε2=n−1+p+q2.\varepsilon_1=\frac{n-1-p-q}{2}, \qquad \varepsilon_2=\frac{n-1+p+q}{2}.

Because p,q≥3p,q\ge3, these are positive and satisfy ε1<ε2<n\varepsilon_1<\varepsilon_2<n. Thus

Γ={ε1,ε2,n},#Γ=3,ε1+ε2=n−1,min⁡Γ=ε1,max⁡Γ=n.\Gamma=\{\varepsilon_1,\varepsilon_2,n\}, \quad \#\Gamma=3, \quad \varepsilon_1+\varepsilon_2=n-1, \quad \min\Gamma=\varepsilon_1, \quad \max\Gamma=n.

Finally,

f2(e)=f1(n)f1(e)f_2(e)=f_1(n)f_1(e)

holds for every integer ee, proving the requested relation at e=ε1e=\varepsilon_1.