The symmetric, "curious dance" between C and C# in 2009-2011 could be due to the fact that "#" is not a alphanumerical character. Some searches for "C#" may hav

The symmetric, "curious dance" between C and C# in 2009-2011 could be due to the fact that "#" is not a alphanumerical character. Some searches for "C#" may have been miscounted as searches for "C" in that period. (But that's just an hypothesis.)