Coupled Klein · nontrivial character — instance data

Definition

HodgeComputerKleinCoupledCharacter

by benediamond · Nov 5, 2026 · Mathlib 0df444a (Lean v4.33.1)

algebraic-geometryhodge-computerklein-coupled-character

The exact fixed polynomials and pole parameter for “Coupled Klein · nontrivial character”, over $\mathbb C$ with coordinates $X_0,X_1,X_2,Y_0,Y_1,Y_2$ :

F=K+Y_0^6+Y_1^6+Y_2^6+t\cdot P.

q=1,\qquad A=X_{0}^{3} \cdot Y_{0}^{3}.

where

\begin{aligned} t&=\frac57 \\ K&=X_0^5\cdot X_1+X_1^5\cdot X_2+X_2^5\cdot X_0 \\ P&=2 \cdot X_{0}^{3} \cdot X_{2} \cdot Y_{1} \cdot Y_{2} + X_{0} \cdot X_{1}^{3} \cdot Y_{0} \cdot Y_{1} + 3 \cdot X_{1} \cdot X_{2}^{3} \cdot Y_{0} \cdot Y_{2} \end{aligned}

Definition code

import Definitions.Def_DiamondCertificate

set_option autoImplicit false
noncomputable section
namespace HodgeComputer.KleinCoupledCharacter
def n : ℕ := 5
def d : ℕ := 6
def F : HodgeComputer.AmbientPoly n := (((((((((((MvPolynomial.X (R := ℂ) (0 : Fin 6)) ^ (5 : ℕ)) * (MvPolynomial.X (R := ℂ) (1 : Fin 6))) + ((((((10 : MvPolynomial (Fin 6) ℂ) * ((MvPolynomial.X (R := ℂ) (0 : Fin 6)) ^ (3 : ℕ))) * (MvPolynomial.X (R := ℂ) (2 : Fin 6))) * (MvPolynomial.X (R := ℂ) (4 : Fin 6))) * (MvPolynomial.X (R := ℂ) (5 : Fin 6))) * MvPolynomial.C (σ := Fin 6) (1 / 7 : ℂ))) + ((((((5 : MvPolynomial (Fin 6) ℂ) * (MvPolynomial.X (R := ℂ) (0 : Fin 6))) * ((MvPolynomial.X (R := ℂ) (1 : Fin 6)) ^ (3 : ℕ))) * (MvPolynomial.X (R := ℂ) (3 : Fin 6))) * (MvPolynomial.X (R := ℂ) (4 : Fin 6))) * MvPolynomial.C (σ := Fin 6) (1 / 7 : ℂ))) + ((MvPolynomial.X (R := ℂ) (0 : Fin 6)) * ((MvPolynomial.X (R := ℂ) (2 : Fin 6)) ^ (5 : ℕ)))) + (((MvPolynomial.X (R := ℂ) (1 : Fin 6)) ^ (5 : ℕ)) * (MvPolynomial.X (R := ℂ) (2 : Fin 6)))) + ((((((15 : MvPolynomial (Fin 6) ℂ) * (MvPolynomial.X (R := ℂ) (1 : Fin 6))) * ((MvPolynomial.X (R := ℂ) (2 : Fin 6)) ^ (3 : ℕ))) * (MvPolynomial.X (R := ℂ) (3 : Fin 6))) * (MvPolynomial.X (R := ℂ) (5 : Fin 6))) * MvPolynomial.C (σ := Fin 6) (1 / 7 : ℂ))) + ((MvPolynomial.X (R := ℂ) (3 : Fin 6)) ^ (6 : ℕ))) + ((MvPolynomial.X (R := ℂ) (4 : Fin 6)) ^ (6 : ℕ))) + ((MvPolynomial.X (R := ℂ) (5 : Fin 6)) ^ (6 : ℕ)))
def A : HodgeComputer.AmbientPoly n := (((MvPolynomial.X (R := ℂ) (0 : Fin 6)) ^ (3 : ℕ)) * ((MvPolynomial.X (R := ℂ) (3 : Fin 6)) ^ (3 : ℕ)))
def q : ℕ := 1
end HodgeComputer.KleinCoupledCharacter

Source

https://github.com/hodge-computer/sextics/blob/83fbf5c9a0afe9136ce4f1ed324d085a2c899bd0/data/klein-coupled-character/instance.rec

Read-back

What the Lean code literally says, in plain math · GPT-6 (OpenAI Codex; independent auditor)

$n$ . The natural number $n$ is defined to be $5$ .

$d$ . The natural number $d$ is defined to be $6$ .

$F$ . In the polynomial ring $R=\mathbb C[X_0,X_1,X_2,Y_0,Y_1,Y_2]$ , with the six indeterminates corresponding, in that order, to the indices $0,1,2,3,4,5$ , the polynomial $F$ is defined by

\begin{aligned} F={}&X_0^5X_1+X_0X_2^5+X_1^5X_2+Y_0^6+Y_1^6+Y_2^6\\ &+\frac{10}{7}X_0^3X_2Y_1Y_2+\frac{5}{7}X_0X_1^3Y_0Y_1+\frac{15}{7}X_1X_2^3Y_0Y_2. \end{aligned}

$A$ . In the polynomial ring $R=\mathbb C[X_0,X_1,X_2,Y_0,Y_1,Y_2]$ , with the six indeterminates corresponding, in that order, to the indices $0,1,2,3,4,5$ , the polynomial $A$ is defined to be $X_0^3Y_0^3$ .

$q$ . The natural number $q$ is defined to be $1$ .

Human review

Endorsed by Shuze Chen · Nov 6, 2026
Confirmed by the moderator at approval.
Endorsed by benediamond · Nov 6, 2026
Confirmed by the mission captain (proposal self-audit).

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