Nanatsu no Ko

"七つの子"
Song
English title	Nanatsu no Ko
Written	Nagoya, Japan
Published	July, 1921
Form	Children's song
Composer(s)	Nagayo Motoori
Lyricist(s)	Ujō Noguchi
Language	Japanese

Nanatsu no Ko (七つの子^?, lit. Seven children, or Seven baby crows, The crow's seven chicks) is a popular Japanese children's song with lyrics written by Ujō Noguchi (野口雨情 Noguchi Ujō) and composed by Nagayo Motoori (本居 長世 Motoori Nagayo). Published in Kin no fune (The golden ship) magazine in July 1921. Nanatsu no ko is used as the departure melody at Isohara Station in Kitaibaraki.

In the manga and anime Detective Conan by Gosho Aoyama, the mail address of the boss of the Black Organization is #969#6261, which reproduces the beginning of Nanatsu no Ko.

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