Exercise

Which of the following codes is a cyclic code in Z/2Z?

The set of vectors consisting of 0000000, 1111111 and all cyclic shifts of 1101000 and 1110010.

The set of vectors consisting of 0000000 and all cyclic shifts of 1000000.

The set of vectors consisting of 0000000, 1111111 and all cyclic shifts of 1010000 and 1111010.

The set of vectors consisting of 0000000, 1111111 and all cyclic shifts of 1100100 and 1101100.