Robin Thicke spends a second week at No. 1 on the Billboard Hot 100 with “Blurred Lines,” featuring T.I. and Pharrell. Pharrell, meanwhile, thanks to Daft Punk’s 3-2 lift with “Get Lucky,” on which he’s featured, becomes the first artist in four years to place songs at Nos. 1 and 2 simultaneously. Imagine Dragons additionally fire up a piece of Hot 100 history, completing a record-establishing trek to the top five.

“Lines” locks up the Hot 100’s top spot as the chart’s top Digital and Airplay Gainer. The track spends a third week at No. 1 on Hot Digital Songs, gaining by 18% to 371,000 downloads sold, according to Nielsen SoundScan, and reaches the top five on Hot 100 Airplay and Streaming Songs: it bound 8-4 on the former chart (96 million all-format audience impressions, up 32%) and 8-5 on the latter (3.7 million U.S. streams, up 6%), according to Nielsen BDS.

“Lines” concurrently notches a second week at No. 1 on Hot R&B/Hip-Hop Songs and a fifth week atop the R&B Songs chart.

“Lines” maintains its command on the Hot 100 with an impressive 18% jump in overall chart points, holding off Daft Punk’s “Get Lucky,” also featuring Pharrell (billed as featuring Pharrell Williams on the song), which climbs 3-2 (up 1%). The track racks a fourth week at No. 1 on the subscription services-based On-Demand Songs chart (2.1 million, down 14%); holds at No. 2 on Streaming Songs (4.7 million, down 12%) and No. 4 on Hot Digital Songs (195,000, up 1%); and charges 6-5 on Hot 100 Airplay (95 million, up 19%).

With Pharrell credited as a featured act on the Hot 100’s top two songs, he’s the first artist to rank at both spots concurrently in almost four years. The Black Eyed Peas last accomplished the feat for four weeks in June/July 2009 when “Boom Boom Pow” spent its last of 12 weeks at No. 1 while follow-up “I Gotta Feeling” waited at No. 2 before the tracks switched positions for two weeks. Among soloists, T.I. had last managed such a double with “Whatever You Like” and “Live Your Life” (the latter title featuring Rihanna) for six weeks in October/November 2008.

“Lucky” dominates the Dance/Electronic Songs chart for a fifth week.

Macklemore & Ryan Lewis’ “Can’t Hold Us,” featuring Ray Dalton, slips 2-3 on the Hot 100 after ruling the tally for five frames (down 7% in overall points). Still, “Hold” continues to gain slightly in airplay, bulleting at No. 2 on Hot 100 Airplay (135 million, up 1%) for a third week. The track also crowns Rap Songs for a ninth week.

Imagine Dragons’ “Radioactive” climbs 6-4 on the Hot 100, reaching the top five for the first time in its record-setting 42nd week. The song bests the 34-week ascent to the region of Florida Georgia Line’s “Cruise,” featuring Nelly, a longevity mark set just three weeks ago. (“Cruise” descends 5-6 on the Hot 100, although it logs a 16th week at No. 1 on Hot Country Songs).

Whereas “Cruise” made its lengthy journey by starting at country before crossing over to pop and adult formats, “Radioactive” has traveled its scenic path by starting at rock (it led Alternative for 13 weeks) before finding support at pop and adult radio; it reaches the Mainstream Top 40 top 10 (14-10) and bullets at its No. 12 peak-to date on Adult Top 40 this week.

“Radioactive,” atop Hot Rock Songs for a 13th week, reaches a new peak on Hot Digital Songs, rising 5-2 (207,000, up 8%) and, as on Mainstream Top 40, enters the top 10 on Hot 100 Airplay (14-10; 69 million, up 22%). It pushes 4-3 on Streaming Songs (4-3; 3.8 million, up 6%).

Justin Timberlake’s “Mirrors” drops 4-5 on the Hot 100, after peaking at No. 2, although it rules Hot 100 Airplay for a fifth week (154 million, down 3%).

Below Florida Georgia Line’s “Cruise” at No. 6, the songs at Nos. 7 through 10 on the Hot 100 remain in place from last week: P!nk’s former three-week Hot 100 No. 1 “Just Give Me a Reason,” featuring fun.’s Nate Ruess (7-7); Selena Gomez’s “Come & Get It” (8-8); Ariana Grande’s “The Way,” featuring Mac Miller (9-9); and Icona Pop’s “I Love It,” featuring Charli XCX, (10-10).

Check Billboardbiz tomorrow (June 20), when all rankings, including the Hot 100, Hot Digital Songs, Hot 100 Airplay, Streaming Songs and On-Demand Songs will be refreshed, as they are each Thursday. [Billboard.biz]