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Tag Archives: numbers
Nature by Numbers
This has been making the rounds of the math blogosphere (blathosphere?), but in case you haven’t seen it yet, check out Cristóbal Vila’s awesome short video, Nature by Numbers. Especially appropriate given that I have been writing about Fibonacci numbers … Continue reading
Computing with decadic numbers
[This is the ninth, and, I think, final in a series of posts on the decadic numbers (previous posts: A curiosity, An invitation to a funny number system, What does "close to" mean?, The decadic metric, Infinite decadic numbers, More … Continue reading
Infinite decadic numbers
To recap: we’ve now defined the decadic metric on integers by where is not divisible by 10, and also . According to this metric, two numbers are close when their difference is decadically small. So, for example, and are at … Continue reading
Posted in arithmetic, convergence, infinity, number theory
Tagged decadic, negative, numbers
7 Comments
The decadic metric
Continuing my series of posts exploring the decadic numbers… in my previous post, I explained that we will define a new “size function”, or metric, different from the usual “absolute value”, and written . Two numbers will be “close to” … Continue reading
Posted in arithmetic, number theory, pattern
Tagged decadic, distance, integers, metric, number line, numbers, padic, soup
5 Comments
An invitation to a funny number system
Consider the equation Solving this equation is no sweat, right? Let’s do it. First, we subtract from both sides: Now we can factor an out of the left side: Now, if the product of two things is zero, one of … Continue reading
Triangunit divisors
Here’s a neat problem from Patrick Vennebush of Math Jokes 4 Mathy Folks: Append the digit 1 to the end of every triangular number. For instance, from 3 you’d get 31, and from 666 you’d get 6,661. Now take a … Continue reading
Posted in number theory, pattern, puzzles
Tagged divisors, numbers, triangular, triangunit, unit
9 Comments
Book Review: The Mystery of the Prime Numbers
Several months ago, Matthew Watkins sent me a review copy of his new book, Secrets of Creation Volume One: The Mystery of the Prime Numbers. It’s taken me a while to get around to reviewing it, but not for lack … Continue reading
Posted in books, number theory, primes, review
Tagged book review, mystery, numbers, prime
3 Comments
Book reviews: Math Jokes 4 Mathy Folks and Easy as Pi
Math Jokes 4 Mathy Folks A few months ago, Patrick Vennebush was kind enough to send me a review copy of his new book, Math Jokes 4 Mathy Folks. It’s a treasuretrove of mathrelated jokes with a huge range of … Continue reading