The next state for the 9 (1001) row is 0 (0000) and the remaining next states are don’t cares, since states 10 through 15 are never reached. We have included rows in this table for the unused states because they are needed to produce don’t cares on the maps. Some may write the state table without these rows and then convert it to this truth table (as we did in the last section). The maps for the next state, with the J section shaded for finding J and K using the quick method, are shown next.
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