论文标题
关于单价函数系数的差异
On the difference of coefficients of univalent functions
论文作者
论文摘要
对于$ f \ in \ nathcal {s} $，在单位磁盘$ \ mathbb {d} $中分析且无关，由$ f（z）= z+s+sum_ {n = 2}^{\ sum_ { $ | a_4 | - | | a_3 | $当$ f \ in \ mathcal {s} $。这在情况下提供了改进的限制，$ n = 3 $的1976年的一般限制$ || a_ {n+1} | - | A_n || a_n || \ le 3.61 \ dots。$其他系数界限，第二和第三hankel nakelys的界限，当$ f \ in \ nathcal in \ nathcal cal {$ a_ 3时，$ f \ n $ a_3 nes $ a_ a $ a_2 = 0 0 = 0。
For $f\in \mathcal{S}$, the class of normalized functions, analytic and univalent in the unit disk $\mathbb{D}$ and given by $f(z)=z+\sum_{n=2}^{\infty} a_n z^n$ for $z\in \mathbb{D}$, we give an upper bound for the coefficient difference $|a_4|-|a_3|$ when $f\in \mathcal{S}$. This provides an improved bound in the case $n=3$ of Grispan's 1976 general bound $||a_{n+1}|-|a_n||\le 3.61\dots .$ Other coefficients bounds, and bounds for the second and third Hankel determinants when $f\in \mathcal{S}$ are found when either $a_2=0,$ or $a_3=0$.
