Information sets as permutation cycles for quadratic residue codes

[摘要] The two casesp=7andp=23are the only known cases where the automorphism group of the[p+1,   (p+1)/2]extended binary quadratic residue code,O(p), properly containsPSL(2,p). These codes have some of their information sets represented as permutation cycles fromAut(Q(p)). Analysis proves that all information sets ofQ(7)are so represented but those ofQ(23)are not.

[学科分类] 数学（综合）