https://www.johndcook.com/blog/2022/10/21/math-origins/ explains V.I. Arnolds comment
"All mathematics is divided into three parts: cryptography (paid for by CIA, KGB and the like), hydrodynamics (supported by manufacturers of atomic submarines), and celestial mechanics (financed by military and other institutions dealing with missiles, such as NASA)."
The article https://www.johndcook.com/non_central_chi_square.pdf sounds interesting:
John D. Cook Upper bounds on non-central chi-squared tails and truncated normal moments (2010). UT MD Anderson Cancer Center Department of Biostatistics Working Paper Series. Working Paper 62.
Abstract. We show that moments of the truncated normal distribution provide upper bounds on the tails of the non-central chi-squared distribution, then develop upper bounds for the former.
A reading protocol is a set of strategies that a reader must use in order to benefit fully from reading the text. Poetry calls for a different set of strategies than fiction, and fiction a different set than non-fiction. It would be ridiculous to read fiction and ask oneself what is the author's source for the assertion that the hero is blond and tanned; it would be wrong to read non-fiction and not ask such a question. This reading protocol extends to a viewing or listening protocol in art and music. Indeed, much of the introductory course material in literature, music and art is spent teaching these protocols.
Mathematics has a reading protocol all its own, and just as we learn to read literature, we should learn to read mathematics. Students need to learn how to read mathematics, in the same way they learn how to read a novel or a poem, listen to music, or view a painting. Ed Rothstein’s book, Emblems of Mind, a fascinating book emphasizing the relationship between mathematics and music, touches implicitly on the reading protocols for mathematics.
spigot is a calculating program. It supports the usual arithmetic operations, square and cube roots, trigonometric and exponential functions, and a few other special functions such as erf.
spigot differs from the average calculating program in that it is an exact real calculator. This means that it does not suffer from rounding errors; in principle, it can keep generating more and more digits of the number you asked for until it runs out of memory.
In particular, if you ask for a complex expression such as sin(sqrt(pi)), then most calculating systems would compute first pi, then sqrt(pi) and finally sin(sqrt(pi)), accumulating a rounding error at each step, so that the final result had a build-up of error and you would have to do some additional error analysis to decide how much of the output you could trust.
spigot, on the other hand, does not output any digit until it is sure that digit is correct, so if you ask for (say) 100 digits of sin(sqrt(pi)) then you can be sure they are the right 100 digits.
Alexandre Stefanov long maintained a list of online math texts and other materials at Geocities, but it appears that his original web site is no longer available. Because these resources may be of interest to our readers, we present here a modified version of Stefanov's list as of November 18, 2009. We welcome corrections or suggested additions to this list.
Mark Chu-Carroll's blog covers many subjects, including mathematics, physics and programming. In this article he describes his design of a programming language suited for an editor (think about a more readable version of TECO's language).
As of 2021-06-21, the site cannot be reached. On 2021-12-22 it is on-line again.
In order to factor (relatively) large semi-primes (i.e. semi-primes larger than 150-bits), you should (probably) just ask YAFU (Yet Another Factoring Utility, https://github.com/DarkenCode/yafu) to try to factor the number for you in parallel using a highly-optimized number field sieve such as GGNFS (GPL General Number Field Sieve) or SIQS (Self-Initialising Quadratic Sieve). By using YAFU I was able to factor a 302-bit semi-prime in a little over half an hour , as opposed to over the course of 72 minutes using Sage’s Quadratic Sieve (QS).
Vincenty's formulae are two related iterative methods used in geodesy to calculate the distance between two points on the surface of a spheroid, developed by Thaddeus Vincenty (1975a) They are based on the assumption that the figure of the Earth is an oblate spheroid, and hence are more accurate than methods such as great-circle distance which assume a spherical Earth.
The first (direct) method computes the location of a point which is a given distance and azimuth (direction) from another point. The second (inverse) method computes the geographical distance and azimuth between two given points. They have been widely used in geodesy because they are accurate to within 0.5 mm (0.020″) on the Earth ellipsoid.