A Bitonic Sequence is a sequence of numbers which is first strictly increasing then after a point strictly decreasing.
According to the definition of a bitonic sequence, we know that a graph of a bitonic sequence can have at most one "peak" and one "valley".
So, why is the sequence
1,3,2,4 not a bitonic sequence?
I have referred the book, "Parallel Computing", by M. J. Quinn.