A method of determining a nucleic acid sequence that includes steps of: (a) contacting a primed template nucleic acid with a series of mixtures for forming ternary complexes, wherein each of the mixtures includes a polymerase and nucleotide cognates for at least two different base types suspected of being present at the next template position of the template nucleic acid; (b) monitoring the next template position for ternary complexes formed by the series of mixtures, wherein a signal state indicates presence or absence of ternary complex formed at the next template position by each individual mixture, thereby determining a series of signal states that encodes a base call for the next template position; and (c) decoding the series of signal states to distinguish a correct base call for the next template position from an error in the base call.