The recurrence is

T(1) = 0

If n > 1, then write m = floor of n/2

T(n) = T(m) + T(n-m) + n-1

Example: T(37) = T(18) + T(19) + 36

Col A: n
Col B: T(n) = number of comparisons needed to mergesort n items
Col C: ceiling of lg(n)
Col D: formula given in problem 12.7, where lg(n) is replaced by ceiling lg(n)
Col E: lg(n!)

A simple closed form formula for T(n)
is n*(ceiling(lg(n))) - 2^(ceiling(lg(n)) + 1

For example, if n = 37, then ceiling(lg(n)) = 6, while 2^(ceiling(lg(n)) = 64.
Thus the formula gives 37*6 - 64 + 1 = 159