Generator-offset property: Difference between revisions

Inthar (talk | contribs)
Inthar (talk | contribs)
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===== Some implications of the above =====
===== Some implications of the above =====
Suppose Q = (α, β, γ) ≠ R = (α, β’, γ’) are the two k-steps in S that project to P. Then T = (α’, β’’, γ’’) projects to I. Here the values in each component differ by at most 1, and α ≠ α’. Either β’’ = β or β’’ = β’. Assume β’’ = β’. Then γ’’ = γ. The cyclic words Λ<sub>1</sub> = the pattern of α and α’, Λ<sub>2</sub> = the pattern of β and β’, and Λ<sub>3</sub> = the pattern of γ and γ’ must form mosses, and Λ<sub>1</sub> = α...αα’. By the assumption β’’= β, Σ<sub>2</sub> has one more R than Σ<sub>3</sub>, and thus:
Suppose Q = (α, β, γ) ≠ R = (α, β’, γ’) are the two k-steps in S that project to P. Then T = (α’, β’’, γ’’) projects to I. Here the values in each component differ by at most 1, and α ≠ α’. The cyclic words Λ<sub>1</sub> = the pattern of α and α’, Λ<sub>2</sub> = the pattern of β and β’, and Λ<sub>3</sub> = the pattern of γ and γ’ must form mosses, and Λ<sub>1</sub> = α...αα’.


* Λ<sub>2</sub> is λβ μβ’, 2 ≤ μ ≤ ceil(n/2).
Suppose Λ<sub>2</sub> is λβ μβ’. Then Λ<sub>3</sub> is a (λ &pm; 1)γ (μ &mp; 1)γ’ mos. Since neither Λ<sub>2</sub> nor Λ<sub>3</sub> are multimosses, and at least one of μ and (μ ∓ 1) are even, it is now immediate that n is odd.
* Λ<sub>3</sub> is a (λ ± 1)γ (μ 1)γ’ mos.


Since neither Λ<sub>2</sub> nor Λ<sub>3</sub> are multimosses, and at least one of μ and 1) are even, it is now immediate that n is odd.
Either β’’ = β or β’’ = β’. Assume β’’ = β’. Then γ’’ = γ, and Λ<sub>3</sub> is a (λ + 1)γ &minus; 1)γ’ mos. Also assume that the first k-step in Σ is Q:
 
We can assume that the first k-step in Σ is Q:
       1 …        n
       1 …        n
  Σ  = Q W(Q, R)  T
  Σ  = Q W(Q, R)  T