ARTICLE SYNOPSIS ...How to spot takeover candidates by Norman S. Wei The shares of Celanese Corp. were trading at 218-1/2 at the close of Oct. 31. They shot up to a high of 247-1/2 on Nov. 3 and closed at 242-1/2--an increase of $24 per share! Integrated Software's stock jumped from 9 to 12- 1/4 over-night on Nov. 3. In late February 1986, Western Airlines' stock jumped from 8-7/8 to 12-1/4 within a week. These were all takeover or merger candidates. Celanese agreed to merge with American Hoechst Corp. for $245 per share. Computer Associates International Inc. acquired Integrated Software for 12-3/8 a share in ...