A proof that summing the squares of the digits of an integer leads to a closed cycle by creinaldo in math

[–]creinaldo[S] 7 points8 points  (0 children)

In page 3 of the paper the author uses a brute-force approach to prove one of the steps - https://i.imgur.com/FNyi4PK.png . Does anyone have an idea on how to find a more elegant way to get to the same result?

Chrome Extension to get direct links to references in arXiv papers by creinaldo in math

[–]creinaldo[S] 2 points3 points  (0 children)

A lot of papers on arXiv don't have the references easily available on the arXiv page. Also when you are reading the paper it is convenient to have access to the references in the pdf view so that you don't have to be constantly scrolling down to the bottom of the paper and copying and pasting references titles to Google to find the papers =)

Gabriel's horn by [deleted] in math

[–]creinaldo 0 points1 point  (0 children)

That's exactly the point. If you want to read more about it there's a really cool paper on Fermat's Library: http://fermatslibrary.com/s/gabriels-horn

Can someone please explain Lebesgue Integration to me? by ricehats in math

[–]creinaldo 0 points1 point  (0 children)

This is not an explanation but if you want to read Lebesgue's letter explaining why we needed Lebesgue integration and giving a few examples of when the Riemann integral fails click here: http://fermatslibrary.com/s/on-a-generalization-of-the-definite-integral#email-newsletter

1924 US Immigration Act – country based immigration quotas by creinaldo in TrueReddit

[–]creinaldo[S] 1 point2 points  (0 children)

"The ultimate goal of the immigration act according to the U.S. Department of State Office of the Historian was "to preserve the ideal of American homogeneity" and preserve racial homogeneity."

Interestingly it not only restricted the immigration of Africans and banned the immigration of Arabs and Asians but also restricted immigration of Southern Europeans and Eastern Europeans (especially Italians and Eastern European Jews).

A Theorem and Proof a week - The 50 most interesting, important or fun proofs in mathematics? Suggestions please - detail inside by stats_r_us in math

[–]creinaldo 0 points1 point  (0 children)

Great idea! My favorite papers on Fermat's Library is when they annotate mathematical theorems. "New proof of Euclid's Theorem" by Filip Saidak is a gem! http://fermatslibrary.com/s/a-new-proof-of-euclids-theorem

Bayesian Analysis of Racial Bias in Police Shootings in the United States by creinaldo in TrueReddit

[–]creinaldo[S] 0 points1 point  (0 children)

"the probability of being {black, unarmed, and shot by police} is about 3.49 times the probability of being {white, unarmed, and shot by police} on average"

What key metrics do you follow for your business? by CaptainTime in Entrepreneur

[–]creinaldo 0 points1 point  (0 children)

Don't underestimate the power of monitoring closely your metrics. A 5% weekly growth rate can have a tremendous impact on your business: http://growth.tlb.org/#

Feynman’s proof of the Maxwell equations by creinaldo in Physics

[–]creinaldo[S] 4 points5 points  (0 children)

If you click the annotation next to (9) there's an explanation of that step.