Try the following GMAT Problem Solving question on finding terms of a general sequence.
Question 48:
In a sequence each term after the first term is one less than twice the previous term. If the third term of the sequence is $t$, then what is the first term expressed in terms of $t$ ?

$\quad 2t1$

$\quad \dfrac{t+1}{2}$

$\quad \dfrac{t+1}{4}$

$\quad \dfrac{t3}{4}$

$\quad \dfrac{t+3}{4}$