There are a batch of 15 articles, and the pages of each article are 1 page, 2 pages, 3 pages... 14 pages and 15 pages of manuscript paper. If these articles are bound into a volume in a certain order, and the page numbers are uniformly numbered, Then the first page of each article is the maximum number of articles with odd page numbers.
有一批文章共15篇，各篇文章的页数分别是1页、2页、3页…14页和15页的稿纸，如果将这些文章按某种次序装订成册，并统一编上页码，那么每篇文章的第一页是奇数页码的文章最多有多少篇．
<gadget id="calculator">7 + 4</gadget>
<output>11</output>

<result>11</result>