manually define page numbers in latex?

Question

I am editing a 100+ page document in latex, document class is "book". The first few pages of the document have roman page numbers, the rest have arabic page numbers starting with one. I.e. the document has page numbers i-iv, followed by pages 1-120. However, want I want is the pages to be: vii-ix, followed by pages 1-120. (reason: I am inserting some other PDF pages preceding the PDF ultimately generated by latex, and this obviously leads to all following page numbers beeing higher).

So how can I increase the roman page numbers to start from a higher number (but not increase the arabic page numbers at the samee time)?

Thank you.

Answer 1

You don't need to use \setcounter{page}{1} when arabic numbers start. This happens automatically:

\documentclass{book}
\begin{document}
\pagenumbering{roman}
\setcounter{page}{3}
a
\newpage
\pagenumbering{arabic}
b
\end{document}

has page iii followed by page 1.

Answer 2

use \setcounter{page}{7} after \begin{document} and if necessary \setcounter{page}{1} when the arabic page numbers start.