A sequence y1,y2,y3,… y_1, y_2, y_3, \dots\,y1,y2,y3,… is defined by
y1=cyn=5yn−1−2,n≥2 \begin{aligned}y_1 &= c \\y_n &= 5y_{n-1} - 2, \quad n \geq 2\end{aligned} y1yn=c=5yn−1−2,n≥2Find an expression for y2 y_2\,y2 in terms of ccc.
Show that y3=25c−12y_3 = 25c - 12y3=25c−12.
Find ∑r=14yr\sum_{r=1}^4 y_r∑r=14yr in terms of ccc.
