[seqfan] Re: Composite numbers n such that digits of prime factors of n are either 4 or 9.

Marc LeBrun mlb at well.com
Thu Sep 24 05:01:23 CEST 2020

>=israel at math.ubc.ca wrote:
> More generally, for every list S of primes we could have a sequence for
> "Composite numbers whose prime factors are in S".  There are lots of those!

Indeed.  That idea's fine to address the naming issue, but let's please try to avoid encouraging a proliferation of pointless sequences!

More information about the SeqFan mailing list