Probably been a while since that has happened. Last artist to not debut #1 and then achieve it weeks later?
What a cool achievement including this one...
"Pentatonix is the first act to chart a pair of albums concurrently in the top five since Prince on the May 21-dated chart, following an outpouring of support for his music following his death on April 21. Previous to Prince, both David Bowie and Whitney Houston also scored the feat, in 2016 and 2012, respectively -- but again, only after their deaths. The last living act to notch a pair of albums in the top five at the same time was Adele on the March 3, 2012-dated chart." - Billboard