The term "base pairs" is, as far as I know, not standard mathematical language. I suspect it is a phrase used in the particular textbook or by the particular instructor you are using.
You might get a response from somebody who knows what you are talking about; but probably not.
So resubmit your questions, defining what it is you are asking about.
You can put this solution on YOUR website! Base pair | Define Base pair at Dictionary.com
www.dictionary.com/browse/base-pair
Base pair definition, any of the pairs of the hydrogen-bonded purine and pyrimidine bases that form the links between the sugar-phosphate backbones of nucleic acid molecules: the pairs are adenine and thymine in DNA, adenine and uracil in RNA, and guanine and cytosine in both DNA and RNA.