Generator-offset property: Difference between revisions

Inthar (talk | contribs)
Inthar (talk | contribs)
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In case 1, let g<sub>1</sub> = (2, 1) &minus; (1, 1), g<sub>2</sub> = (1, 2) &minus; (2, 1), and g<sub>3</sub> = (1, 1) &minus; (''n''/2, 2) = (&minus;''n''/2*g<sub>1</sub> &minus; g<sub>1</sub> &minus; ''n''/2*g<sub>2</sub>) mod e. We assume that g<sub>1</sub>, g<sub>2</sub> and e are '''Z'''-linearly independent. We have the chain g<sub>1</sub> g<sub>2</sub> g<sub>1</sub> g<sub>2</sub> ... g<sub>1</sub> g<sub>3</sub> which visits every note in ''S''.  
In case 1, let g<sub>1</sub> = (2, 1) &minus; (1, 1), g<sub>2</sub> = (1, 2) &minus; (2, 1), and g<sub>3</sub> = (1, 1) &minus; (''n''/2, 2) = (&minus;''n''/2*g<sub>1</sub> &minus; g<sub>1</sub> &minus; ''n''/2*g<sub>2</sub>) mod e. We assume that g<sub>1</sub>, g<sub>2</sub> and e are '''Z'''-linearly independent. We have the chain g<sub>1</sub> g<sub>2</sub> g<sub>1</sub> g<sub>2</sub> ... g<sub>1</sub> g<sub>3</sub> which visits every note in ''S''.  


Because of the SGA assumption, ''S'' is constant-structure; in particular, since  (g<sub>3</sub> + g<sub>1</sub>) &minus; (g<sub>2</sub> + g<sub>1</sub>) is the chroma of the mos generated by (g<sub>1</sub> + g<sub>2</sub>), it is apparent that g<sub>2</sub> and g<sub>3</sub> subtend the same number of steps.
Since ''S'' is GO it is well-formed with respect to (g<sub>2</sub> + g<sub>1</sub>), which must generate a mos subset. Hence (g<sub>3</sub> + g<sub>1</sub>), the imperfect generator of the mos generated by (g<sub>2</sub> + g<sub>1</sub>), subtends the same number of steps as (g<sub>2</sub> + g<sub>1</sub>). Thus g<sub>2</sub> and g<sub>3</sub> subtend the same number of steps.


Let ''r'' be odd and ''r'' ≥ 3. Consider the following abstract sizes for the interval class (''k''-steps) reached by stacking ''r'' generators:
Let ''r'' be odd and ''r'' ≥ 3. Consider the following abstract sizes for the interval class (''k''-steps) reached by stacking ''r'' generators: