# Details for entry $$A_4(7,2)$$

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## Exact bounds

• d2 ( ) : 25704928

## Lower bounds

• echelon_ferrers (
optimal [(), (0, 1), (0, 1, 2, 3), (0, 1, 2, 3, 4, 5), (0, 1, 2, 3, 4, 6), (0, 1, 2, 3, 5, 6), (0, 1, 2, 4), (0, 1, 2, 4, 5, 6), (0, 1, 2, 5), (0, 1, 2, 6), (0, 1, 3, 4), (0, 1, 3, 4, 5, 6), (0, 1, 3, 5), (0, 1, 3, 6), (0, 1, 4, 5), (0, 1, 4, 6), (0, 1, 5, 6), (0, 2), (0, 2, 3, 4), (0, 2, 3, 4, 5, 6), (0, 2, 3, 5), (0, 2, 3, 6), (0, 2, 4, 5), (0, 2, 4, 6), (0, 2, 5, 6), (0, 3), (0, 3, 4, 5), (0, 3, 4, 6), (0, 3, 5, 6), (0, 4), (0, 4, 5, 6), (0, 5), (0, 6), (1, 2), (1, 2, 3, 4), (1, 2, 3, 4, 5, 6), (1, 2, 3, 5), (1, 2, 3, 6), (1, 2, 4, 5), (1, 2, 4, 6), (1, 2, 5, 6), (1, 3), (1, 3, 4, 5), (1, 3, 4, 6), (1, 3, 5, 6), (1, 4), (1, 4, 5, 6), (1, 5), (1, 6), (2, 3), (2, 3, 4, 5), (2, 3, 4, 6), (2, 3, 5, 6), (2, 4), (2, 4, 5, 6), (2, 5), (2, 6), (3, 4), (3, 4, 5, 6), (3, 5), (3, 6), (4, 5), (4, 6), (5, 6)] (if conjecture about Ferrers Diagram Rank-Metric Codes is true: 25704928 with optimal [(), (0, 1), (0, 1, 2, 3), (0, 1, 2, 3, 4, 5), (0, 1, 2, 3, 4, 6), (0, 1, 2, 3, 5, 6), (0, 1, 2, 4), (0, 1, 2, 4, 5, 6), (0, 1, 2, 5), (0, 1, 2, 6), (0, 1, 3, 4), (0, 1, 3, 4, 5, 6), (0, 1, 3, 5), (0, 1, 3, 6), (0, 1, 4, 5), (0, 1, 4, 6), (0, 1, 5, 6), (0, 2), (0, 2, 3, 4), (0, 2, 3, 4, 5, 6), (0, 2, 3, 5), (0, 2, 3, 6), (0, 2, 4, 5), (0, 2, 4, 6), (0, 2, 5, 6), (0, 3), (0, 3, 4, 5), (0, 3, 4, 6), (0, 3, 5, 6), (0, 4), (0, 4, 5, 6), (0, 5), (0, 6), (1, 2), (1, 2, 3, 4), (1, 2, 3, 4, 5, 6), (1, 2, 3, 5), (1, 2, 3, 6), (1, 2, 4, 5), (1, 2, 4, 6), (1, 2, 5, 6), (1, 3), (1, 3, 4, 5), (1, 3, 4, 6), (1, 3, 5, 6), (1, 4), (1, 4, 5, 6), (1, 5), (1, 6), (2, 3), (2, 3, 4, 5), (2, 3, 4, 6), (2, 3, 5, 6), (2, 4), (2, 4, 5, 6), (2, 5), (2, 6), (3, 4), (3, 4, 5, 6), (3, 5), (3, 6), (4, 5), (4, 6), (5, 6)])
) : 25704928
• improved_cdc_lower_bound ( ) : 25704928
• layer_construction ( ) : 25704928
• cdc_lower_bound ( ) : 24208613
• gilbert_varshamov ( ) : 424218
• cdc_average_argument ( ) : 131318
• trivial_4 ( ) : 2
• trivial_2 ( ) : 0

## Do you have better bounds?

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