Among the numbers \(5\),
\(15\),
\(28\),
\(47\)
identify the number which is not a member of the sequence
\(\left (2n^{2} - 3\right )_{n=1}^{\infty }\).
Consider the sequences \(\left (a_{n}\right )_{n=1}^{\infty }\)
and \(\left (b_{n}\right )_{n=1}^{\infty }\)
where \(a_{n} = 2^{n}\)
and \(b_{n} = n^{2} - 1\),
respectively. Identify a true statement in the terms of these sequences.