Vocalist's third week at number one

East London vocalist Tinchy Stryder and N-Dubz have notched their third week at the top of the singles chart with the aptly titled song Number 1.

It is Ghanaian born Stryder's biggest hit so far.

His previous single Take Me Back (featuring Taio Cruz) debuted at number three and spent 14 weeks in the Top 40.

The Official UK Charts Company, which compiles the countdown, said never before had a number one single featured the words "Number 1" in the title.

La Roux remained at number two position in the singles chart with their song In For The Kill, while Tiny Dancer (Hold Me Closer) - a collaboration between Ironik, Chipmunk and Sir Elton John - charted at number three above Scottish sensation Calvin Harris.

Harris's dance-pop track I'm Not Alone is the first single from the 25-year-old's second album.

Lady Gaga's Poker Face remained in fifth spot.

In the album charts, Bob Dylan held on to top spot as he marked almost 40 years after his last number one record.

His last chart topper was New Morning which was released in October 1970, reaching number one on November 28.

Together Through Life is Dylan's seventh UK number one, his 33rd studio album and his 53rd album, including compilations and soundtracks. Lady Gaga's The Fame moved up a spot to number two while Lilly Allen's It's Not Me It's You charted in third.