+ (setq arts (gnus-sorted-difference
+ articles (mapcar 'car gnus-agent-article-alist)))
+ ;; Assume that articles with smaller numbers than the first one
+ ;; Agent knows are gone.
+ (setq first (caar gnus-agent-article-alist))
+ (when first
+ (while (and arts (< (car arts) first))
+ (pop arts)))