I have been working on this problem for about 5 days now and I still can't figure out the answer. One of my friends at school even asked someone from his work who is an electrical engineer that minored in math and he couldn't get it. the given series is 2,1,1,(15/7),390...

that is two, one, one, fifteen halfs, three hundred ninty...

if anyone can figure out the pattern and/or the formula for this series I would greatly appreciate it. I know that it is a sud n+1= ( )a sub n

but out side of that I have no idea what the solution could be. Any help on this would be greatly appreciated, again. Thanks.