Subject: Combinations of Numbers.
Who are you: Student
Here is the problem:
A "train of length 5" is a row of blocks whose combined
length is 5. Here are some examples: 1-2-2, 2-1-2, 1-3-1, 5, 1-4.
If you use identical blocks in a different order,
this is a separate train. How many trains of length 5 are there? Come up
with a formula for the number of trains of length n.
I know all the lengths:
I know the relationship is that the number of your combinations
for the next number will be the combination before doubled. My question
is,...how do I write a formula for that?