What is relation? your 1 to 6 is just my proof. my 2011/2 out of

I wrote next year ,2012 ,even number,we can get f.

Your 1,2,you give too strong condition,f is bijection...

I think ,though you are smart,your major is not math.F(x)is unique and r(x) may or not unique.So,r(x)=x+1005,r(x)=x+1006....