title: Investigating combinations of English currency denominations.
url: http://projecteuler.net/problem=31

desc: |
  In England the currency is made up of pound, £ and pence, p, and there are eight coins in general circulation:
  1p, 2p, 5p, 10p, 20p, 50p, ñ (100p) and £ (200p).
  It is possible to make £ in the following way:
  1£ + 150p + 220p + 15p + 12p + 31p
  How many different ways can £ be made using any number of coins?
solution: Define the target value as 200 to simplify
