Knutsen & Ludvigsen is a musical duo from Trondheim, Norway, who wrote and performed various songs for children. They released seven albums from 1970 to 1983, two of which received Spellemannprisen - the Norwegian Grammy. They had several #1 hits, including "Grevling i taket" (Badger in the ceiling), "Hallo! Hallo!" and "Dum og deilig" (Stupid and gorgeous). They officially split up in 1987. The duo consists of Øystein Dolmen and Gustav Lorentzen (1947 - 2010).