# coding=utf-8 name = 'pascal/3' slug = 'pascal’s triangle' description = '''\

The first five rows of the Pascal's triangle look like this:

    1
   1 1
  1 2 1
 1 3 3 1
1 4 6 4 1

Each row begins and ends with 1. Every other element can be obtained as a sum of the two values above it. Write the predicate pascal(I,J,N) that returns the J-th value in the I-th column of the Pascal's triangle. Your solution should return exactly one answer for any input (the I and J arguments start counting with 0; you can assume that 0 ≤ JI).

?- pascal(0, 0, N).
  N = 1.
?- pascal(2, 1, N).
  N = 2.
?- pascal(4, 3, N).
  N = 4.
''' hint = {}