But the 2nd and 3rd terms are still wrong!

They must be what you get when you substitute n=2 and n=3 into

the general term [2(n-1)+1/4]

But watch what happens when you substitute n=2 into [2(n-1)+1/4]

You get 

[2(2-1)+1/4] = [2(1)+1/4] = [2+1/4] = [8/4+1/4] = 9/4 and 9/4 is NOT 2*1/4

See?

Also watch what happens when you substitute n=3 into [2(n-1)+1/4]

You get 

[2(3-1)+1/4] = [2(2)+1/4] = [4+1/4] = [16/4+1/4] = 17/4 and 17/4 is NOT 4*1/4.

The sequence is botched.  The induction proof I gave you is correct.

Edwin