set PageCountINDD to PageCount div 4
repeat
if PageCountINDD / 8 = PageCountINDD div 8 then exit repeat
set PageCountINDD to PageCountINDD + 1
end repeat
PageCountINDD

Hi. Your intent is unclear. Let’s say you have a 19 page document… Nigel’s approach would give you 24 as a result, which is divisible by 8, but isn’t within your existing page range. If you want to just advance by 8, you could do:

tell application "Adobe Acrobat Pro"
repeat with whatever from ((count pages) div 4) to count pages by 8
whatever--{4,12}
end
end

not an one-liner, but this solution does not add anything if the number of pages is dividable by 8

set PageCountINDD to numberOfPages() -- pseudo handler for application specific code
set modulo to PageCountINDD mod 8
if modulo is not 0 then
set PageCountINDD to PageCountINDD + 8 - modulo
end if

PS: I’m using this in Acrobat for a brochure print (dividable by 4) to add empty pages

repeat while ((count pages of mainDoc) mod 4 is not 0)
tell mainDoc to insert pages after (count pages of mainDoc) from emptyPageDoc number of pages 1 starting with 1
end repeat

Stefan’s method’s more suitable than mine for the purpose decribed in post #8, since it doesn’t raise numbers which are already multiples of 8. Yvan’s successfully one-lined it, but it can also be done mathematically like this: