Theory of feedback shift registers with invertors

The existing theory of linear sequential circuits is extended to include linear circuits modified by the addition of invertors. Essentially, these contralinear circuits are analysed by embedding them in higher-order linear circuits. It is shown that a general contralinear sequential circuit is equivalent to a collection of contralinear feedback shift registers, each containing, at most, one invertor. The feedback shift register containing a single invertor in its feedback path is considered in some detail.