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In this note, we study the classification of $\mathbb{Z}_4$ -codes. For some special cases $(k_1,k_2)$ , by hand, we give a classification of $\mathbb{Z}_4$ -codes of length $n$ and type $4^{k_1}2^{k_2}$ satisfying a certain condition. Our exhaustive computer search completes the classification of $\mathbb{Z}_4$ -codes of lengths up to $7$ .
Citation: |
Table 1. Length 1
| | | | | | | |
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Table 2. Length 2
| | | | | | | |
| | | | 1 | 1 | 2 | |
| | | | | 2 | 0 | 1 |
| | |
Table 3. Length 3
| | | | | | | |
| | 1 | 1 | 2 | 3 | ||
| | | 2 | 2 | 0 | 5 | |
| | 3 | 2 | 1 | 3 | ||
| 0 | 3 | 1 | 3 | 0 | 1 | |
1 | 1 | 7 |
Table 4. Length 4
| | | | | | | |
| | 1 | | 1 | 3 | 4 | |
| | | 3 | 2 | 1 | 23 | |
| | 4 | | 2 | 2 | 6 | |
| 0 | 3 | 3 | 3 | 0 | 9 | |
1 | 1 | 17 | | 3 | 1 | 4 | |
| 0 | 4 | 1 | | 4 | 0 | 1 |
1 | 2 | 16 | |||||
2 | 0 | 18 |
Table 5. Length 5
| | | | | | | |
| | 1 | 1 | 4 | 5 | ||
| | | 4 | 2 | 2 | 67 | |
| | 5 | 3 | 0 | 63 | ||
| 0 | 3 | 6 | 2 | 3 | 10 | |
1 | 1 | 33 | 3 | 1 | 55 | ||
| 0 | 4 | 4 | 3 | 2 | 10 | |
1 | 2 | 54 | 4 | 0 | 14 | ||
2 | 0 | 49 | 4 | 1 | 5 | ||
| 0 | 5 | 1 | 5 | 0 | 1 | |
1 | 3 | 29 | |||||
2 | 1 | 121 |
Table 6. Length 6
| | | | | | | |
| | 1 | | 1 | 5 | 6 | |
| | | 6 | 2 | 3 | 157 | |
| | 6 | 3 | 1 | 587 | ||
| 0 | 3 | 12 | | 2 | 4 | 16 |
1 | 1 | 58 | 3 | 2 | 212 | ||
| 0 | 4 | 11 | 4 | 0 | 179 | |
1 | 2 | 149 | | 3 | 3 | 22 | |
2 | 0 | 121 | 4 | 1 | 112 | ||
| 0 | 5 | 5 | | 4 | 2 | 16 |
1 | 3 | 134 | | 0 | 20 | ||
2 | 1 | 499 | | 5 | 1 | 6 | |
| 0 | 6 | 1 | | 6 | 0 | 1 |
1 | 4 | 47 | |||||
2 | 2 | 500 | |||||
3 | 0 | 381 |
Table 7. Length 7
| | | | | | | |
| | 1 | 1 | 6 | 7 | ||
| | | 7 | 2 | 4 | 319 | |
| | 7 | 3 | 2 | 3247 | ||
| 0 | 3 | 21 | 4 | 0 | 2215 | |
1 | 1 | 93 | 2 | 5 | 23 | ||
| 0 | 4 | 27 | 3 | 3 | 648 | |
1 | 2 | 359 | 4 | 1 | 2257 | ||
2 | 0 | 256 | 3 | 4 | 43 | ||
| 0 | 5 | 17 | 4 | 2 | 565 | |
1 | 3 | 503 | 5 | 0 | 429 | ||
2 | 1 | 1728 | 4 | 3 | 43 | ||
| 0 | 6 | 6 | 5 | 1 | 204 | |
1 | 4 | 283 | 5 | 2 | 23 | ||
2 | 2 | 2896 | 6 | 0 | 27 | ||
3 | 0 | 1955 | 6 | 1 | 7 | ||
| 0 | 7 | 1 | 7 | 0 | 1 | |
1 | 5 | 70 | |||||
2 | 3 | 1582 | |||||
3 | 1 | 5184 |
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