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Sessions for West's sixth solo effort begin to take shape in early 2013 in his own personal loft's living room at a Paris hotel. Determined to "undermine the commercial", he once again brought together close collaborators and attempted to incorporate Chicago drill, dancehall, acid house, and industrial music. Primarily inspired by architecture, West's perfectionist tendencies led him to contact producer Rick Rubin fifteen days shy of its due date to strip down the record's sound in favor of a more minimalist approach. Initial promotion of his sixth album included worldwide video projections of the album's music and live television performances. Yeezus, West's sixth album, was released June 18, 2013 to rave reviews from critics. It became the rapper's sixth consecutive number one debut, but also marked his lowest solo opening week sales. Def Jam issued "Black Skinhead" to radio in July 2013 as the album's lead single. On September 6, 2013, Kanye West announced he would be headlining his first solo tour in five years, to support Yeezus, with fellow American rapper Kendrick Lamar accompanying him along the way.

What artist did Kanye go on tour with while promoting album number six?
Kendrick Lamar