Mathematicians submit proof of Erdős Coloring Conjecture

Fifty years ago, several mathematicians at a dinner party were discussing graphs (points and lines, not chart graphs), and the generalization if you make the edges connecting a point (vertex) with another, able to connect multiple points. While working out the minimal number of colors in general, they found it to be an interesting problem, to test out and prove the next day… Well, that solution, to Erdős, Faber, and Lovász’ problem was delayed for years and years!

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Severe weather alerts with a simple Python script

If like many you have been starting gardens and planting rather than traveling and visiting in recent months, there is one important thing to consider lately – severe weather reports including frost on your crops. I noted there was a little red (!) alert icon on an Android weather widget, but there seems to be no such alert for desktop computer or Linux computer or phone. It is a fairly simple to make this alert though with a simple script:

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Introducing the new EMP-proof Ham Radio Repeater Listing

If you have been using Amateur radio for some time you may know about the app connected to repeater listing, which lets you keep an offline record of radio repeaters and a topo-map, on your Linux computer, tablet, phone, or even Android phone. But what would you do during an EMP or solar event causing extended downtime and damage of all computer devices?

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Listening for a callsign on DMR with

These past few weeks have certainly been trying for some communities with power outages, winter weather and utility failures. Ham radio is a very good way to communicate in your local community, but what if lots of other people are on the local repeater? What if you want a notification if your child or buddy is calling you, but not every other kerchunk or distracting story on the local repeater? If you have a DMR digital radio and id and digital repeater nearby, the tools on may help – and help save your battery leaving a radio on all day 🙂

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