I am trying to implement qr-codes (2d "barcodes"). The part with generating error correction codes is difficult to me, and I've found a tutorial on the www that helps me understanding the math behind it.
http://www.thonky.com/qr-code-tutorial/part-2-error-correction/
I can follow the steps until the writer introduces the term "$α^{78}x^{11}$" in the second section called "Multiply generator polynomial by first coefficient of the above polynomial" (the first sentence there is "First coefficient of the above polynomial: $α^{178}$").
Where does the $x^{11}$ come from?
This is obviously basic math, I feel a bit ashamed to ask this... (first question here on math.sx)