PAGES OF 13
Paramond the paranoid parakeet is very superstitious about the number 13. Recently he got ahold of a large book with 800 pages.
Excluding the cover, there are no unnumbered pages. The first page is numbered "1" and the last page is numbered "800". At first he was only going to rip out the 13th page, but this would not be enough. So he went through the whole book ripping out all the pages that had page numbers with the digits 1 and/or 3.
How many pages remained?