{"id":5894,"date":"2015-11-19T12:22:30","date_gmt":"2015-11-19T11:22:30","guid":{"rendered":"http:\/\/www.walkingrandomly.com\/?p=5894"},"modified":"2015-11-19T12:22:30","modified_gmt":"2015-11-19T11:22:30","slug":"carnival-of-mathematics-128","status":"publish","type":"post","link":"https:\/\/walkingrandomly.com\/?p=5894","title":{"rendered":"Carnival of Mathematics #128"},"content":{"rendered":"

Welcome to the 128th Carnival of Mathematics<\/a>, the latest in a mathematical blogging tradition that’s been ongoing for over 8 years now!<\/p>\n

Facts about 128<\/strong><\/p>\n

It’s said that every number is interesting and 128 is no exception.\u00a0128 is the largest number which is not the sum of distinct squares whereas it\u00a0is the smallest number n such that dropping the first and the last digit of n leaves its largest prime factor (thanks, Number Gossip<\/a>).<\/p>\n

Wikipedia tells us that it is divisible by the total number of its divisors, making it a refactorable number<\/a>. Additionally,\u00a0128 can be expressed by a combination of its digits with mathematical operators thus 128 = 28 – 1<\/sup>, making it a Friedman number<\/a> in base 10.<\/p>\n

128 was also the number of kilobytes of memory available in the magnificent computer shown below.<\/p>\n

\"\u00a9<\/a><\/p>\n

 <\/p>\n

The Princeton Companion to Applied Mathematics<\/strong>
\nI recently received a copy of the The Princeton Companion to Applied Mathematics<\/a>\"\" and it’s just beautiful, definitely recommended as a christmas gift for the maths geek in your life. The companion’s editor, Nick Higham, has written a few blog posts about it – Companion authors speaking about their work<\/a>, Famous Mathematicians and The Princeton Companion<\/a>\u00a0and How to Use The Princeton Companion to Applied Mathematics<\/a>.<\/p>\n

\"\"<\/a>\"\"<\/p>\n

We have a lot of problems, and that’s a good thing<\/strong>
\n‘Diane G’ submitted this advanced knowledge problem<\/a>\u00a0— great practice for advanced mathematics. This blog<\/a> is amazing and posts practice problems every Monday and advanced problems every Wednesday.<\/p>\n

Linear Programming<\/strong>
\nLaura Albert McLay of Punk Rock Operations Research<\/a> (great blog title!) submitted two great posts: Should a football team run or pass? A game theory and linear programming approach<\/a> and dividing up a large class into discussion sections using integer programming<\/a><\/p>\n

Francisco Yuraszeck submitted 10 Things You need to know about Simplex Method <\/a>saying ‘This article is about the basics concepts of Linear Programming and Simplex Method for beginers in Operations Research.<\/em>‘<\/p>\n

Computation<\/strong>
\nStuart Mumford demonstrates various ways of computing the first 10,000 numbers<\/a> in the Fibonacci Sequence using Python — and some are\u00a0much<\/strong> faster than others. Laurent Gatto followed up with a version in R<\/a>.<\/p>\n

Cleve Moler, the original developer of MATLAB, looks at three algorithms for finding a zero of a function of a real variable:<\/p>\n