It's the ATOMIC number for technetium.
The Big Bang Theory Season 6, Episode 8
I mean, he works with lasers
and ATOMIC magnets.
The Big Bang Theory Season 7, Episode 24
"Penny, just as Oppenheimer came to regret
his contributions to the first ATOMIC bomb...
The Big Bang Theory Season 1, Episode 2
Atomic magnets?
The Big Bang Theory Season 7, Episode 24
a woman is dividing the ATOMIC weight
of the best noble gas
The Big Bang Theory Season 9, Episode 8