import Data.List n x 0 = 1 n x y | y < 0 = 0 n x y | x < 0 = 0 main = do
Standard input is empty
[1] [3,1] [6,7,1] [10,25,15,1] [15,65,90,31,1] [21,140,350,301,63,1] [28,266,1050,1701,966,127,1] [36,462,2646,6951,7770,3025,255,1] [45,750,5880,22827,42525,34105,9330,511,1] [55,1155,11880,63987,179487,246730,145750,28501,1023,1]