Problem Analysis #7

18.94s
4,261 toks
Problem Statement

Let

G=(1000122010011100102120001201)G = \begin{pmatrix} 1 & 0 & 0 & 0 & 1 & 2 & 2 \\ 0 & 1 & 0 & 0 & 1 & 1 & 1 \\ 0 & 0 & 1 & 0 & 2 & 1 & 2 \\ 0 & 0 & 0 & 1 & 2 & 0 & 1 \end{pmatrix}

be a generator matrix of a ternary linear code CF37C \subset \mathbb{F}_3^7. It is known that the order of the group of monomial automorphisms of CC is 24. How many generator matrices produce codes that are monomially equivalent to C\mathcal{C}?\

Ground Truth
652138905600
Execution Trace
Reasoning Process

[THOUGHT] Let me analyze this problem step by step.

We have a generator matrix G for a ternary linear code C ⊂ F_3^7. The code has dimension k=4 and length n=7.

A generator matrix is in standard form [I_k | P] where I_k is the k×k identity matrix.

Two codes are monomially equivalent if one can be obtained from the other by:

  1. Permuting the coordinates (columns)
  2. Multiplying each coordinate by a non-zero scalar

The group of monomial automorphisms of C has order 24.

The number of generator matrices that produce codes monomially equivalent to C can be computed as follows:

The total number of ways to choose a generator matrix for any code monomially equivalent to C is:

  • Total monomial transformations on F_3^7: The monomial group M_n(F_3) has order n! × (q-1)^n = 7! × 2^7 for n=7 and q=3
  • But we need to count generator matrices, not just codes

Actually, let me think more carefully. A generator matrix G produces a code C. Two generator matrices G1 and G2 produce monomially equivalent codes if and only if there exists a monomial matrix M such that the row space of G1·M equals the row space of G2.

The number of generator matrices for a fixed code C of dimension k over F_q with length n is:

  • The number of ordered bases of a k-dimensional vector space over F_q
  • This is (q^k - 1)(q^k - q)(q^k - q^2)...(q^k - q^(k-1)) = |GL_k(F_q)|

For k=4 and q=3: |GL_4(F_3)| = (3^4-1)(3^4-3)(3^4-9)(3^4-27) = 80 × 78 × 72 × 54

The monomial group M_7(F_3) has order 7! × 2^7 = 5040 × 128 = 645120

The number of codes monomially equivalent to C is |M_7(F_3)| / |Aut(C)| = 645120 / 24 = 26880

The number of generator matrices producing codes monomially equivalent to C is: (Number of equivalent codes) × (Number of generator matrices per code) = 26880 × |GL_4(F_3)|

Let me compute this. [/THOUGHT] [PYTHON] import math

Parameters

n = 7 # length k = 4 # dimension q = 3 # field size (ternary)

Order of GL_k(F_q) - number of generator matrices for a fixed code

gl_k_q = 1 for i in range(k): gl_k_q *= (qk - qi) print(f"|GL_4(F_3)| = {gl_k_q}")

Order of monomial group M_n(F_q)

monomial_group_order = math.factorial(n) * (q-1)**n print(f"|M_7(F_3)| = {monomial_group_order}")

Order of automorphism group of C

aut_C = 24 print(f"|Aut(C)| = {aut_C}")

Number of codes monomially equivalent to C

num_equivalent_codes = monomial_group_order // aut_C print(f"Number of equivalent codes = {num_equivalent_codes}")

Number of generator matrices producing codes monomially equivalent to C

num_generator_matrices = num_equivalent_codes * gl_k_q print(f"Number of generator matrices = {num_generator_matrices}") [/PYTHON]

Tool Output
[PYTHON OUTPUT] |GL_4(F_3)| = 24261120 |M_7(F_3)| = 645120 |Aut(C)| = 24 Number of equivalent codes = 26880 Number of generator matrices = 652138905600 [/PYTHON OUTPUT]
Reasoning Process

[THOUGHT] The calculation shows that:

  • |GL_4(F_3)| = 24261120 (number of generator matrices for a single code)
  • |M_7(F_3)| = 645120 (order of the monomial group)
  • Number of codes monomially equivalent to C = 645120/24 = 26880
  • Total number of generator matrices = 26880 × 24261120 = 652138905600 [/THOUGHT]

\boxed{652138905600}

Final Model Output
652138905600

Comparative Analysis (P7) (Average across runs)

Avg Time Taken

Qwen3-30B-A3B-2507
1905.6
Gemma-3-27B
873.1
Deepseek-R1-distill-Qwen-32B (high)
168.1
Gemini-3-Pro-Preview
76.1
EXAONE-4.0.1-32B (high)
74.4
Grok-4.1-fast
71.4
GPT-oss-20B (high)
56.1
Solar-Pro-2 (31B)(high)
55.1
Deepseek-V3.2
41.8
HCX-007(high)
35.0
GPT-5.1 (high)
25.1
Llama-VARCO-8B-Instruct
24.7
Claude-Opus-4.5
17.4
A.X-4.0 (72B)
13.5

Avg Token Usage

Gemini-3-Pro-Preview
13535.7
Grok-4.1-fast
11559.7
Qwen3-30B-A3B-2507
10081.0
Solar-Pro-2 (31B)(high)
9138.0
GPT-oss-20B (high)
8720.3
Deepseek-V3.2
5870.7
HCX-007(high)
5705.3
Deepseek-R1-distill-Qwen-32B (high)
4983.0
EXAONE-4.0.1-32B (high)
4507.3
Claude-Opus-4.5
4192.7
GPT-5.1 (high)
4129.3
Llama-VARCO-8B-Instruct
3571.3
A.X-4.0 (72B)
3021.3
Gemma-3-27B
2368.7