Republic of Mathematics blog

Posts Tagged ‘prime numbers

A curious number exploration

Posted by: Gary Ernest Davis on: May 6, 2011

Benjamin Vitale (@BenVitale) tweeted that he followed 203 people on Twitter and is a prime number. Alex Bogomolny (@CutTheKnotMath) observed that if (digits base 10) then has a factor of unless one of . A quick computational search (using Mathematicaâ„¢) yields the following numbers (base 10 digits) for which is prime: 10, 20, 203, 230, […]

Happy mathematical new year: 2011 is the sum of 11 consecutive prime numbers

Posted by: Gary Ernest Davis on: January 1, 2011

xOn December 31, 2010 @mathematicsprof posted two interesting tweets: @mathematicsprof FINALLY, a prime number year 2011 …. first one since 2003. x @mathematicsprof 2011 is also the sum of 11 CONSECUTIVE prime numbers: 2011=157+163+167+173+179+181+191+193+197+199+211 x Two prime numbers are “consecutive” if they follow one upon the other, in the collection of prime numbers. So, for […]