UPD:
Weight of column
Number of 1’s in column
Constructing n-bit SEC-DED Hsiao Code
First use all possible weight-1 columns
Then all possible weight-3 columns
Then weight-5 columns, etc.
Until n columns formed
Number check bits is
Minimizes number of 1’s in H-matrix
Less hardware and delay for computing syndrome
Disadvantage: Correction logic more complex
Это все, что нашел. В отрыве от контекста совсем ничего не понятно.