Conseco Inc. said it is calling for the redemption on Dec. 7 of all the 800,000 remaining shares outstanding of its $1.875 Series A convertible preferred stock at $26.805 a share. The insurance concern said all conversion rights on the stock will terminate on Nov. 30. Until then, Conseco said the stock remains convertible into common stock at the rate of 1.439 shares of common stock for each share of preferred stock, which is equivalent to a conversion price of $17.50 a common share. In New York Stock Exchange trading Friday, Conseco closed at $19.50, down 25 cents.