diff --git a/nico.py b/nico.py
index be5f913..4fd8a28 100644
--- a/nico.py
+++ b/nico.py
@@ -25,11 +25,11 @@ CONFIG: dict[str, DbConfig] = { 'mysql': { 'driver':    'mysql',
 DB = DatabaseManager (CONFIG)
 Model.set_connection_resolver (DB)
 
-KIRIBAN_VIEWS_COUNTS: set[int] = { *range (1_000, 10_000, 1_000),
-                                   *range (10_000, 1_000_001, 10_000),
-                                   194, 245, 510, 810, 114_514, 1_940, 2_450, 5_100,
-                                   19_400, 24_500, 51_000, 93_194, 2_424, 242_424, 1_919, 4_545,
-                                   194_245, 245_194, 510_245 }
+KIRIBAN_VIEWS_COUNTS: list[int] = sorted ({ *range (1_000, 10_000, 1_000),
+                                            *range (10_000, 1_000_001, 10_000),
+                                            194, 245, 510, 810, 114_514, 1_940, 2_450, 5_100,
+                                            19_400, 24_500, 51_000, 93_194, 2_424, 242_424, 1_919,
+                                            4_545, 194_245, 245_194, 510_245 })
 
 class VideoInfo (TypedDict):
     contentId:      str
@@ -143,6 +143,8 @@ def get_kiriban_list (
                                                 .where ('views_count', '>=', kiriban_views_count)
                                                 .get ()) })
         for code in targets:
+            if code in [kiriban[1]['contentId'] for kiriban in kiriban_list]:
+                continue
             video_info = get_video_info (code)
             if video_info is not None:
                 kiriban_list.append ((kiriban_views_count, video_info,