## Visually stunning math concepts which are easy to explain

Math StackExchange has a great list of "visually stunning math concepts which are easy to explain."

## Martin Gardner undiluted

Princeton University Press recently published "Undiluted Hocus-Pocus: The Autobiography of Martin Gardner." I've not reviewed the book since these days I pretty much only interview authors and living authors at that. So, no review from me, but I highly recommend Shecky's review and Shecky's first impressions at Math Tango.

What inspired to blog this afternoon was an email I received from Andrew S. DeSio, Director of Publicity for Princeton University Press. Andrew has asked me to help spread the word that Martin Gardner really did write his own autobiography. Here's an excerpt from Andrew's message.

"Since the book has released some critics of the bio have claimed the book was posthumously pieced together by friends of the famed math writer and that the new biography is a collaboration between the Press and friends of Gardner. This is simply not true. Prior to his death, Martin Gardner wrote a complete manuscript of his autobiography. While some of his dearest friends helped us fine tune the project, this book is absolutely his own. Our math editor Vickie Kearn and I would like the opportunity to refute this claim and so we are hoping your blog might be the perfect forum for us to post a “Letter” with our official statement on the book."

I have to say that in all of my numerous dealings with Princeton University Press I have never ever sensed any action that might be out of integrity. In particular, I've had a few email exchanges with their math editor Vickie Kearn and I even interviewed her for one of my podcasts and, if Vickie says that Martin Gardner wrote his autobiography himself, I believe her.

Here is Vickie's letter. And, here is an excerpt from Martin Gardner's original manuscript, courtesy of Princeton University Press.

## Who Wrote Martin Gardner’s Autobiography?

By Vickie Kearn, Mathematics Editor, Princeton University Press

Once we began to promote Undiluted Hocus Pocus: The autobiography of Martin Gardner, a few people asked me “Who wrote the book?” I initially thought they were confusing a biography with an autobiography but now that I have read a few reviews on amazon, I understand why they asked the question. Some believe that Gardner’s friends put together bits and pieces of things that Martin Gardner wrote. So to clarify things, here is the back story about the publication of this book.

I never met Martin Gardner. I never talked with him on the phone. But, we did write letters to one another for almost 25 years. No one writes letters anymore so when I receive one, I always get excited—especially when it is from someone like Martin Gardner. His letters were always full of fun information and sometimes they concerned book projects we were working on. The letters were always written on a typewriter and corrected by hand in ink, often green. He wrote in small script and it sometimes took a while to sort out the handwriting but the letters were always a treasure trove and worth the effort to decipher.

When Martin’s son, Jim Gardner, contacted me and asked if Princeton University Press would be interested in publishing Martin’s autobiography, I was thrilled. I could not think of a book I would more like to publish. As with many people, Martin Gardner had a huge amount to do with my becoming a math major so being able to do something for him was a fantastic opportunity.

When Jim sent the manuscript I started laughing because it looked like an extremely long letter. It was written with the same typewriter and edited in the same way as his letters. I have attached a page from the manuscript in case you never corresponded with Martin Gardner.

Jim and I talked for a long time about Martin’s wishes for the manuscript and we decided that we would change as little as possible in the manuscript. We could not ask the author his opinion about any changes so we kept asking ourselves would Martin like any changes we planned before we made them. We did correct typos and filled in all the ??? he had sprinkled throughout the manuscript. We confirmed some dates and the order in which events took place.

There are a few places in the manuscript where there is some repetition. Martin had many interests and we knew some people would go only to the chapters that interested them. So, in cases where we thought that might happen, we allowed the repeated material to stand.

Some people ask why it took so long to publish the book after Martin’s death. He finished the manuscript a few months before he died and passed it to his son to decide what to do with it. With any large estate, there are lots of decisions to make and time passes quickly. People who knew Martin well have found some wonderful stories in the book that they never heard before. Other people wish there was more in the book about other things and wonder why he included what he did. We will never know the answer to that question but I do know the answer to:

Who wrote Martin Gardner’s autobiography? He did!

## Is it divisible by 7? Death by regular expression

Here is a fun question at Quora:

How does one determine whether a number is evenly divisible by 7?

There are some remarkably geeky answers. Those of you who write code might enjoy the second answer, by Anders Kaseorg.

Enjoy!

## Carnival of Mathematics submission deadline is 6/1

A friendly reminder:

I'll be hosting the next Carnival of Mathematics. Please check out this URL to learn more about the carnival, to vist past carnivals, or to submit your blog article for #99. Submission deadline is 6/1/13.

## A new approach to mental math

I received an email from Anton Prosolov, a programmer from Norway. His site, King of Mnemonics, sells software that Anton developed, and a novel he wrote.

I have invented a brand new approach to mental math that focuses on something people are good at (which is memory) rather than something they're bad at (which is arithmetics).

For the first time in history, ANY person can now learn how to perform truly amazing calculations in his/her head - things like weekdays, cubic roots and square roots...

Anton asked for me to plug his work. I like what he's doing (although I've not used his software or read his novel.) So, I offered him a plug but I made him work for it. I emailed him some questions about what he's up to. Below are Anton's responses. Enjoy!

**You have a fascination with Pythagoras. Why is that? And, who were the Pythagoreans?**

The Pythagoreans were a mathematical / religious cult in ancient Greece. This combination of mathematics and the supernatural is a perfect fit for me, since I needed a reason WHY people would want to learn my Algorithms. The reason is of course to gain immense power and knowledge in a different dimension called the Other Side (that's what my novel is about).

**So, there was a dark side to the Pythagoreans?**

Yes. My novel depicts several true historic occurrences, and one of them is the murder of their fellow Pythagorean Hippasus due to his discovery of irrational numbers. Like I said, they were sort of a cult. Of course, since this is a fictional novel, I made them even MORE sinister than they actually were.

**What was Pythagoras famous for, other than for the Pythagorean Theorem?**

He was one of the earliest famous cult leaders, with lots of capricious rules and prohibitions.

**What is your novel about?**

My novel is about the struggles of the (evil) Pythagoreans to gain access to an other dimension called the Other Side (with the help of my 5 magic Algorithms). Fortunately, their efforts are being sabotaged by mysterious self-fulfilling Prophecies.

**Your software helps people to learn and practice several techniques that use mnemonics, right?**

That's correct!

**What is a mnemonic and how do mnemonics help with things like difficult multiplications and date calculations?**

Well, Wikipedia defines a mnemonic as a "learning technique that aids information retention". I do have some genuine mnemonics, such as this poem that is actually the multiplication table (it's used in the Absolute Power Algorithm):

fact dense fogs warm suns defy

ares ably reign fierce aides rely

roger swam duct rescue nora

lug's bergs saved beside aura

wergem oiner bown webnew

beldi wolm nelect wifew

fewgwe siwo lesta biol

However, for the most part, you have to memorize several tables in order to do my Algorithms (12 tables in total). This is (technically speaking) NOT a mnemonic. Nevertheless, it's something that involves memory (rather than arithmetics), which is why "King of Mnemonics" is still a fitting name for my software. By the way, utilizing long-term memory (which people are good at) rather than arithmetics (which people are bad at) is precisely the reason why ANYONE can do my Algorithms. This is a brand new approach (invented by me) and the only one that works for ordinary people (I know, because my wife and friends can now calculate weekdays, square and cubic roots in their head because of King of Mnemonics).

**What does the "Absolute Power Algorithm" calculate?**

You can calculate things like 794 * 586 in your head (two 3-digit numbers where all digits are different). However, this is the most difficult Algorithm of the 5 and I do NOT claim that anyone can do it (in fact, my novel is called "Are you the reincarnation of Pythagoras ?", and he or she is the only person in the world (besides the evil Pythagorean Grand Master) who can do the Absolute Power Algorithm quickly enough (under 1 minute). That person is the world's only hope, because it's the most important Algorithm on the Other Side.

**Is there a next project for you?**

I have some ideas for other Algorithms (not necessarily mathematical), but you won't see them for a while, since I have to do them in my spare time, and it took me 10 years to finish my currect project. It would speed things up a lot if I could do this full-time, which is my dream.

## More podcasts coming up in 2013

In 2012 I began my podcast interview series, Inspired By Math!, where I interview people who are inspired by Math and who are inspiring others. I started the series with Keith Devlin on Valentine's Day and have published 15 podcasts altogether, including one with Michael Schrenk on Webbots, Spiders, and Screen Scrapers which was not in the "Inspired by Math" series but I included it because web crawlers are a big interest of mine.

In 2013 I plan to do more podcasts, including more computer-related ones that spark an interest in computing and in mathematical thinking. I started this blog more than five years ago and it took me four of those years to realize that I like to have conversations with people much more than I enjoy writing. I've written plenty of proposals, marketing pieces, press releases, and even ghost-authored a semi-technical article that got published in a professional journal. So, I just assumed that blogging would be the natural way to share my passion about Math. But, this audio interviewing thing captures my heart and mind much more than writing so I'm hoping to do 30 or more podcasts in the coming year. (There, I've said it. Now I have to do it.)

In an effort to make it easy for you to subscribe to the podcasts I've set up an Itunes channel and an RSS feed.

If you're an Itunes person you can subscribe to the series here:

https://itunes.apple.com/us/podcast/sol-ledermans-podcast/id588254197

If RSS is your thing, you can point your reader here:

http://feeds.feedburner.com/InspiredByMath

If you want to browse the set of podcasts, just click here:

http://wildaboutmath.com/category/podcast/

In case you're wondering who I might interview in the coming year, I'm making my list now of who I'm hoping is willing to indulge me. And, I've put the word out that I'm looking for candidates. I've gotten some great suggestions at MathStackExchange. Shecky gave me some great suggestions at his great blog. See the comments at this article.

I should also mention that Shecky's interview series (he does his via email) is outstanding. You can find his interviews here.

Who do you think I should be interviewing in 2013? Who do you know, or know of, who has made a difference in the Math world, who has helped to make Math more accessible, that I should be talking to? That person can be a blogger, a teacher, a mathematician, computer programmer, business person, toy or puzzle maker, or be in any field. Please leave a comment with your ideas.

Have a Happy New Year!

## Interview at Math-Frolic Blog

Shecky Riemann over at the Math-Frolic Blog has an interview series going on. The Math-Frolic interviews, as Shecky has named them, has so far interviewed seven of us in the math community.

1) Pat Ballew of Pat's Blog

2) Presh Talwalkar of Mind Your Decisions

3) Joselle Kehoe of Mathematics Rising

4) John Golden of Math Hombre

5) James Grime of SingingBanana

6) Patrick Honner of MrHonner.com

7) Sol Lederman of Wild About Math

Check out my interview here, and all the others as well.

## Numberphile channel on Youtube

I just learned about this new Youtube channel.

Numberphile provides viewers a new perspective when it comes to numbers. From Googols and Googolplexs to Root2, this channel offers anyone the “Perfect Number”. Currently, they have a video on the sounds of Pi, here is the link to check it out – http://www.youtube.com/user/numberphile/featured

Here's a nice Numberphile video, very appropriate for Pi Day: "Professor Ed Copeland on a strange occurrence of Pi involving bouncing balls."