[R] Changing Index Labelling on x axis

[WRAY NICHOLAS]

Hi  I have a vector of data (for example c(2,3,4,5,4,3,2)

data<-c(2,3,4,5,4,3,2)
plot(data)

I simply want to up the index values along the x axis by 2, so that instead of
1, I have 3, instead of 2 I have 4 etc etc.  Despite ages playing around with
the axis function I can't get it to work, and keep getting weird error messages.
 This is likely to be laughably simple but if someone can help me out I'd be
grateful

Thanks Nick W
	[[alternative HTML version deleted]]