The 'Billionaire' collaborator dragged Rihanna's Loud from pole position and battled a strong new entry in the shape of Ritual by White Lies to reach number one.
Plan B's The Defamation Of Strickland Banks and a climbing Ellie Goulding round out the top five, while Rumer's Seasons Of My Soul dives down six spots to ten with their arrival.
Also taking a heavy fall are chart veterans Mumford & Sons, whose Sigh No More falls from five to 11 in its 68th week of release.
By comparison, Mayhem by Imelda May, Olly Murs's self-titled album and Good Ol' Fashioned Love by The Overtones all experience a healthy boost, leaping a combined total of 20 places to become this week's 15, 16 and 17 respectively.
The top ten in full:
1. (-) Bruno Mars: 'Doo-Wops & Hooligans'
2. (1) Rihanna: 'Loud'
3. (-) White Lies: 'Ritual'
4. (2) Plan B: 'The Defamation Of Strickland Banks'
5. (7) Ellie Goulding: 'Lights'
6. (3) Cee Lo Green: 'The Lady Killer'
7. (8) Tinie Tempah: 'Disc-Overy'
8. (6) Adele: '19'
9. (9) Eliza Doolittle: 'Eliza Doolittle'
10. (4) Rumer: 'Seasons Of My Soul'
Source: Official Charts Company
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