# GENERALIZED PELL SEQUENCES RELATED TO THE EXTENDED GENERALIZED HECKE GROUPS ${\bar{H}}$3,q AND AN APPLICATION TO THE GROUP ${\bar{H}}$3,3

• Birol, Furkan (Institute of Sciences, Department of Mathematics, Balikesir University) ;
• Koruoglu, Ozden (Necatibey Faculty of Education, Department of Mathematics, Balikesir University) ;
• Sahin, Recep (Faculty of Arts and Sciences, Department of Mathematics, Balikesir University) ;
• Demir, Bilal (Necatibey Faculty of Education, Department of Mathematics, Balikesir University)
• 투고 : 2018.09.06
• 심사 : 2018.10.29
• 발행 : 2019.03.25
• 255 7

#### 초록

We consider the extended generalized Hecke groups ${\bar{H}}_{3,q}$ generated by $X(z)=-(z-1)^{-1}$, $Y(z)=-(z+{\lambda}_q)^{-1}$ with ${\lambda}_q=2\;cos({\frac{\pi}{q}})$ where $q{\geq}3$ an integer. In this work, we study the generalized Pell sequences in ${\bar{H}}_{3,q}$. Also, we show that the entries of the matrix representation of each element in the extended generalized Hecke Group ${\bar{H}}_{3,3}$ can be written by using Pell, Pell-Lucas and modified-Pell numbers.

#### 키워드

Extended generalized Hecke groups;Generalized Pell sequence;Pell-Lucas numbers;modified-Pell numbers

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