The application of the (plain) biflectivity (bif) led to the construction of the tecots and subsequent derivation of the lexors as analogs of chapters. However, as observed, the mechanism was not entirely perfect and did not account for the pair of lexors, 1 and 9. The two were constructed in an artificial manner from the remaining small subset of verses that were not properly biflected. This is now resolved via the enhancement of biflectivity with the introduction of its dual notion of cobiflectivity.
A duality can be established between chapters and verses whereby they would exhibit a type of mutual symmetry. Let c:v represent a given verse v in some chapter c. Extending the notation, c:v-w can be thought of as a range of consecutive verses from v to w in chapter c. For instance 25:10-20 stands for the 11 verses, 10 through 20, in chapter 25. Leaving out any specific verse, the shorthand notation c: can be thought of as the set of all verses in chapter c. Symmetrically, leaving out the chapter, the shorthand notation :v is the dual notion representing the set of all chapters containing the given verse v. For instance :15 is the set of all chapters containing verse 15. In particular, :1 has 114 chps, as all chps have verse 1. At the other extreme, :286 is a one-element set containing only chp 2. Similarly, the notation c-d:v stands for the (perhaps proper) and not necessarily consecutive subset of chapters among the set of consecutive chapters from c to d that contain verse v. For instance, 70-76:40 is the set of three nonconsecutive chps {70, 74, 75} out of the seven consecutive chps, 70 - 76, that are long enough to have the verse 40. If none of the chapters within the range c to d contains the verse v this set can be empty. For instance 100-111:15 is an empty set as none of the chapters from 100 to 111 contains the verse 15 as they are all small chapters. From this vantage point, chapters and verse acquire a form of duality where they are seen on equal footing, as chps represent sets of verses, and dually, verses represent sets of chps.
In light of this chp-verse reciprocal symmetry, it is natural to envision the dual notion of cobiflectivity (cobif) on chps as the flip-side of biflectivity on verses. Recall, the set of verses were partitioned into disjoint numbered and 0-numbered blocks. Likewise, the set of chps are partitioned into disjoint subsets as follows: Let T = {1, 9} be the subset containing the two chps 1 and 9, and similarly, C = {2 - 8, 10 - 114} be the set of the remaining chps. The set of all chps is then, D = T ∪ C. Note, T consists of the only two chps with no 0-numbered tetrons. The complement set, C by contrast contains all 0-numbered tetrons. Observe the reversal of the roles in comparison with the partitioning of the set of verses. The disjoint subsets T and C of chapters, here, are the counterparts of the subsets T and V of verses, there. Similarly, D, as the set of all chapters, corresponds to W, the set of all verses. The respective cardinalities are: ∣D∣ = ∣T∣ + ∣C∣ = 2 + 112 = 114. Note, the sum of the digits on both sides is 6. The corresponding sum for verses was 19. Together they form 619, the 114th prime.
The cobif on chps is implemented in the same way, with two mirrors A and B, where A acts on D while B acts on C, only. The operation begins with the A action on chp 1, followed by the B action, proceeding forward alternating between the two, as before, until chp 9 is reached (via A). Continuing again simply retraces the proceeding chps in the sequence. The cycle thus obtained is the dual tecot. This is the only tecot as it encompasses all chps. Chp one is the left cotetron with chp 9 as its dual right cotetron.
The dual tecot, (consisiting entirely of chps), analogously, splits into a pair of left and right colexors, each, of length 57, (114/2), bounded by the pair of cotetrons, chps 1 and 9, resp. The colexors 1 and 9 are the cobif counterpart of lexors. They are to chps what tetrons are to verses.