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Tame automorphisms with multidegrees in the form of arithmetic progressions

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 نشر من قبل Jiantao Li
 تاريخ النشر 2011
  مجال البحث
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Let $(a,a+d,a+2d)$ be an arithmetic progression of positive integers. The following statements are proved: (1) If $amid 2d$, then $(a, a+d, a+2d)inmdeg(Tame(mathbb{C}^3))$. (2) If $a mid 2d$, then, except for arithmetic progressions of the form $(4i,4i+ij,4i+2ij)$ with $i,j inmathbb{N}$ and $j$ is an odd number, $(a, a+d, a+2d) otinmdeg(Tame(mathbb{C}^3))$. We also related the exceptional unknown case to a conjecture of Jie-tai Yu, which concerns with the lower bound of the degree of the Poisson bracket of two polynomials.



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