`a_1=1` ,`a_(k+1)=2(a_k-1)`

`a_(1+1)=2(a_1-1)`

`a_2=2(1-1)=2(0)=0`

`a_3=2(a_2-1)=2(0-1)=2(-1)=-2`

`a_4=2(a_3-1)=2(-2-1)=2(-3)=-6`

`a_5=2(a_4-1)=2(-6-1)=2(-7)=-14`

The first five terms of the sequence are `1,0,-2,-6,-14`

`a_1=1` ,`a_(k+1)=2(a_k-1)`

`a_(1+1)=2(a_1-1)`

`a_2=2(1-1)=2(0)=0`

`a_3=2(a_2-1)=2(0-1)=2(-1)=-2`

`a_4=2(a_3-1)=2(-2-1)=2(-3)=-6`

`a_5=2(a_4-1)=2(-6-1)=2(-7)=-14`

The first five terms of the sequence are `1,0,-2,-6,-14`