What? MMM is learning Combinatorics!? Looks like she is playing with the bell sequence now: bell[n] = number of ways to partition of the set {1, 2, 3, ..., n}
e.g. n = 3: {1, 2, 3} {1} {2 3} {1, 2} {3} {1, 3} {2} {1} {2} {3} so, bell[3] = 5
MMM wonders how to compute the bell sequence efficiently.
输入解释
T -- number of cases for each case: n (1 <= n < 2^31)