Salishan Paraffins Problem:
Given an integer n, output the chemical structure of all
paraffin molecules for i<=n, without repetition and in 
order of increasing size. Include all isomers, but no 
dupicates. The chemical formula for paraffin molecules is
C(i)H(2i+2). Any representation for the molecules could 
be chosen, as long as it clearly distinguishes among
isomers.
 
Solution is based on theory of free and oriented trees
(see Knuth, D. The Art of Computer Programming, Vol. 1)

The correct numbers are:
1, 1, 1, 2, 3, 5, 9, 18, 35, 75, 159, 335, 802, 1858, 4347, ...

The program takes one parameter: the integer n.
