“Sixteen sodium atoms walk into a bar… followed by Batman” (bar joke)

“A guy walks into a bar…” is a typical form of what has been called the “bar joke.” An unusual variation of the joke is:
 
“Sixteen sodium atoms walk into a bar, followed by Batman.”
 
The chemical symbol for sodium is “Na.” The Batman television show theme is: “Na-na-na-na-na-na-na-na-na-na-na-na-na-na-na-na, Batman!”
 
“Sodium x 16 = BATMAN” was cited on Twitter on December 17, 2010. “Sodium sodium sodium sodium sodium sodium sodium sodium sodium sodium sodium sodium sodium sodium sodium sodium. BATMAN” was cited on Twitter on February 28, 2011. “What do Batman & 16 Sodium atoms have in common? Na Na Na Na Na Na Na Na Na Na Na Na Na Na Na Na” was cited on Twitter on March 23, 2012.
 
“Sixteen sodium atoms walk into a bar, shortly followed by batman” was cited on Twitter on March 30, 2013. Several images explain the joke.
       
   
YouTube
The Batman Theme Song
M-Power Addict
Uploaded on Aug 16, 2008
The Batman Theme Song,
 
Twitter
MitchiriNakiusagi
‏@OchotonidKnight
Sodium x 16 = BATMAN
1:26 PM - 17 Dec 2010
 
Twitter
Ja Punzalan
‏@jaapunzalan
Sodium sodium sodium sodium sodium sodium sodium sodium sodium sodium sodium sodium sodium sodium sodium sodium. BATMAN.
7:08 AM - 28 Feb 2011
 
Twitter
Reverend Chapman
‏@Wadatahmydamie
Sodium sodium sodium sodium Sodium sodium sodium sodium Sodium sodium sodium sodium Sodium sodium sodium sodium
BATMAN!
9:43 PM - 14 Mar 2011
 
Twitter
Ntsias Vaj
‏@gvicious
What do Batman & 16 Sodium atoms have in common? Na Na Na Na Na Na Na Na Na Na Na Na Na Na Na Na
2:27 PM - 23 Mar 2012
 
Facebook
Stale Joke Central
April 1, 2012 ·
what does batman and 16 sodium atoms have in common?
NA NA NA NA NA NA NA NA NA NA NA NA NA NA NA NA
   
Twitter
Oli
‏@OliverWare
Sixteen sodium atoms walk into a bar, shortly followed by batman.
4:36 AM - 30 Mar 2013
 
Twitter
Robo
‏@RoboPilgrim
Sixteen sodium atoms walk into a bar. Followed by Batman.
5:59 AM - 30 Mar 2013
 
Engineering.com
Top 10 STEM Puns
Shawn Wasserman posted on February 03, 2014
(...)
10. What do Batman and 15 Sodium atoms have in common?
NaNaNaNaNa NaNaNaNaNa NaNaNaNaNa BATMAN!
   
reddit
16 sodium atoms walk into a bar…... (self.Jokes)
submitted July 2, 2014 by raspheart
followed by batman!....
   
Viralnove
Here Are 21 Jokes So Clever You Probably Won’t Get Them. #10 Is Perfection.
JULY 2, 2014
(...)
5.) Sixteen sodium atoms walk into a bar… followed by Batman.
 
reddit
Sixteen sodium atoms walk into a bar followed by Batman. (self.Jokes)
submitted March 2, 2015 by philosorapper