( n, k, d) Just the check bits; append an identity matrix for data bits
(25, 1,25)  0x0000000000ffffff  0000000000000000000000000000000000000000111111111111111111111111
(38, 2,25)  0x0000000fff000fff  0000000000000000000000000000111111111111000000000000111111111111
    0000000000000000000000111111000000111111000000111111000000111111
    0000000000000000000111000111000111000111000111000111000111000111
    0000000000000000001011011001011001011001011001011001011001011001
    0000000000000000001101101010101010101010101010101010101010101010