1.11 F‘ibonates函数的变种，略过。
1.12 题目：
The following pattern of numbers is called Pascal‘s triangle.
1
1 1
1 2 1
1 3 3 1
1 4 6 4 1
......
The numbers at the edge of the triangle are all 1, and each number inside the triangle is the sum of the two numbers above it.35 Write a procedure that computes elements of Pascal‘s triangle by means of a recursive process.
只要按照如下公式计算即可:
number_at(row, line)
number_at(1,N)=1
number_at(N,N)=1
number_at(N,M)=number_at(N-1,M-1)+number_at(N-1,M)
Exercise 1.11---1.12 Pascal's Triangle
原文：http://www.cnblogs.com/linghuaichong/p/3973152.html