Question

Write a possible explicit rule for the nth term of the sequence: 5, 10, 20, 40, 80, ...

Answer 1

Let \(s_0=5\). Then \(s_n=2\cdot s_{n-1}\), where \(n\geqslant1\).

Answer 2

Hi, an=2 X an-2 + an-1 for a1= 5 , a2 = 10 , a3 = 20 , a4 = 40 end a5 = 80.