Ultimate tables, interesting lists, fascinating sequences and incredible calculations

[rdstern]

This is my bid to tempt maths camps and maths clubs to introduce R-Instat, because it provides some maths and related fun. A bonus will then be that schools who have access to R-Instat also have a powerful and easy to use statistics package, but none of the titles above are really statistical. But they all involve columns of data - and a statistics package is a column calculator.

A related point is that I have always thought our main "market" was spreadsheet users who need more than a spreadsheet (for their statistical work). It is now clearer to me that we should include potential users who don't (yet) use a spreadsheet.

And my agenda also includes the point that if R-Instat is simple enough to introduce to school users, then it is easy enough for all our other potential users.

I'd like others to think of more cool stuff, but here are my 4 aspects so far.
1) Ultimate Tables:
This came from my grandson (Michael) who wanted to write a program to take 1, 2, 3, ... times any number he chose, and give the column of results.

a) It is now quite easy to do the above - and he chose the 78 times table.
b) He noticed the calculator is similar to the one on his phone (but ours is for columns)
c) Then he wanted the columns to be longer - so we did it for 2,000,000 rather than 20! (Our grid is not limited to a million!)
d) Then he noticed the power button and asked for that sort of table so x1 ^ 8. (That's quite big when you consider 2,000,000 ^ 8!

Interesting Lists

We can find many more but here is a list of dinosaurs:

I wonder which is the dinosaur with the longest name. Maybe we could sort them in descending order of that?

Fascinatinating sequences

The first 1000 primes and the first 1000 Fibonacci numbers can be a good start perhaps. What other interesting sequences could we add?

Incredible calculations

Now 2 ^ 9 = 512. So what is 2 million to the power 9. Can we do it exactly and write it out? So, can we do exact calculations with big numbers?

Yes we can - with the gmp package.

I propose a special maths_camp keyboard for our calculator:
For reference, without the keyboard the results above show:
gmp::as.bigq(x1^9) in the second column and then the correct gmp::as.bigq(x1)^9 in the third column.

Want bigger numbers? Well (without the keyboard try: gmp::factorialZ(gmp::asbigq(x1)) Even 65 is quite big!

Or did you know that factorize(34455342) = 2 * 3 * 101 * 56857

I also like the isprime function and there are more! Nice keyboard it could be - if we do that!

[rdstern]

I was looking for more on prime numbers. Here is an interesting site called Prime Pages.

There I downloaded the first 1 million primes - and there are 50 million there. It said that it was quicker to generate them, so I wonder about having keys (on our integer keyboard) to do that? There might be a variety, showing different ways. I saw thast one way uses regex, so that's fun too? Could we use purrr for example? This site is interesting.

But for R-Instat could we generate the first n prime numbers larger than y. Then we could use this in a date frame of length n. I didn't see the code for that?
I would also still like to be able to time commands as suggested in #6264.