Sunday, September 15, 2019

Wednesday, September 04, 2019

Further results on "Grantham's Problem"

While it is gratifying to see a mathematics paper published, it is sometimes even more gratifying to see that paper cited, because it means that someone cares about the original publication.

A decade ago, I mentioned that someone had addressed a question I asked in a 2001 paper, which he called "Grantham's problem."

Now he and two authors have pushed the computations further, in the paper "Quadratic Frobenius pseudoprimes with respect to x2 + 5x + 5".

The results put conditions on a pseudoprime with two prime factors. The known heuristics for the existence of pseudoprimes give ones with many prime factors, so it is not surprising, but it is good to see this evidence.