Osomatsu-kun
Japanese title: おそ松くん
Type: TV
Source: Manga
Episodes: 56
Status: Finished Airing
Aired: Feb 5, 1966 to Mar 25, 1967
Broadcast: Saturdays at 19:30 (JST)
Duration: 25 min per ep
Rating: PG - Children
Studios: Studio Zero
Producers: Mainichi Broadcasting System
Genres: Comedy
Demographics: Shounen

A wacky comedy about identical sextuplets causing wild pranks. Each episode features 2 stories. 

(Source: AniDB)

Osomatsu-kun was Mainichi Broadcasting's first entry into the anime broadcasting. (Until the broadcast of in 2012, the network did not air an anime adaptation of a Shounen Sunday manga for 45 years.) The series later aired on Tokyo 12 Channel (later known as TV Tokyo) between the late 1960s and early 1970s. Osomatsu-kun was never broadcast again after the 1970s, and the original prints were thought to be lost until they were found in storage at the Senrioka studio of Mainichi Broadcasting in 1990. The series was finally released on DVD between 2001 and 2003.