What exactly do they mean when they say "Non-trvial zeros" in reffrence to the RH?
non trivial solutions to a rhe are solutions that are not trivial or ones that arent zero
Zeros other than the negative integers. The zeroes at negative integers are obvious, and do not effect the interesting properties the other zeroes do.
In other words the RH says
z is a negative integer
that is x=1/2+i y for some real number y
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