We choose to host $141$th Carnival in December because $22$nd of this month is celebrated as National Mathematics Day of India. Indian legendary Mathematician Srinivasa Ramanujan was born on $22$nd December $1887$. In order to recognize his immense contribution towards Mathematics the Government of India has declared Ramanujan's birthday to be celebrated every year as the National Mathematics Day of India.
To start with let us first take a look into some interesting facts about number 141.
1. A crazy sequential representation of $141$ written in terms of $1$ to $9$ in increasing as well as decreasing order (taken from http://arxiv.org/abs/1302.1479) is as follows $$141 = 1 + 2.3.4 + 5.6 + 7 + 89 = 9 + 87 + 6.5 + 4.3 + 2 + 1$$ 2. $141 = 3.47$ is a semiprime ( a natural number that has only two prime factors, not necessarily distinct) and $A001358(46) =141$, where the description of $A001358$ can be found here {https://oeis.org/A001358}. Interestingly, prior to this we celebrated $129$th Carnival of Mathematics and eventually $129$ was also a semi-prime.
We will now move on to the posts that make up this months carnival.
Mark Dominus shared with us a nice article titledLet's decipher a thousand-year-old magic square. His discourse is motivated by a magic square carved at the entrance of Parshvantha Temple at Khajuraho in Madhya Pradesh, India.
John Cook shared with us a blog post An integral with a couple lessons which illustrates in context to computing definite integrals two principles very nicely - (1) keep in mind the distinction between a definition and a computational technique, and (2) you might not have to do as much work as it seems.
Peter has shared with us the post titled Why the Number Line Freaks Me Out. This is a nice post which describes different types of computable numbers starting from whole numbers and at the end of it has talked about non-computable numbers which can not be understood by human mind.
Artem Kaznatcheev has provided us with the link of his post Fusion and sex in protocells & the start of evolution which in a way justifies that Theoretical biology is becoming increasingly mathematized. Most exciting is the introduction of tools from theoretical computer science and the analysis of algorithms. Here these tools, along with broader themes from computation, are used to analyze if the fusing parts of sex are essential for getting evolutionary dynamics going. The post combines fundamental biology with some fun math while summarizing, criticising, and expanding on a recent preprint.
Lucy Rycroft-Smith has shared with us his blog post Mathemethics: the dark and desirable 007 side to numbers that refutes the argument that mathematics is useless, and explores some of the thrilling narratives around mathematical, desirable skills.
Who have more sisters: boys or girls?a nice puzzle shared to us by the author Rob Eastaway.This seemingly simple question/puzzle was first posed to the author by Hugh Hunt a couple of years ago. The puzzle turns out to have a number of interesting twists - a couple of which haven't been resolved. For example, how does the fact that girls tend to live longer than boys affect the answer? It's not obvious - and might call for a computer simulation.
In order to recognize his immense contribution towards Mathematics the Government of India has declared Ramanujan's birthday to be celebrated every year as the National Mathematics Day of India.