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Saki (1, 2, 3)—pen name of Hecto Hugh Munro (1870–1916)—was a writer, known for his short stories that are often biting satires sometimes veering to the macabre.

Saw this great observation by Ruud de Rooij (via Robin Houston): Combinatorics can be a bit weird sometimes: the number of ways to arrange N Tetris pieces into a 2-by-2N rectangle is the Nth Fibonacci number squared.

The Sanskrit word tāta (“father”) is sometimes used affectionately for a younger person.

Just writing down what I know, for future reference.

In 2000, Douglas Adams made an interesting observation that I keep returning to.

TLDR: I hesitate to recommend this to anyone as it’s finicky to set up and may go away, but just in case: Google Sheets has an “Extensions -> AppSheet -> Create an app” that gives an easier interface for editing a sheet from phone (stuff like updating a d…

Yesterday I read a nice post called “doubly dual shuffles”, which1 pointed out something about the classic algorithm for shuffling an array (i.e. sampling a uniformly random permutation of it).

The question The following verse occurs twice in the (critical edition of the) Rāmāyaṇa, and four times in the Mahābhārata: सर्वे क्षयान्ता निचयाः पतनान्ताः समुच्छ्रयाः ।

Sanskrit has a rich tradition of Chitrakavya (roughly, constrained writing).

Tom Lehrer got into Harvard in 1943 at age 15, and it is said that the following poem he wrote (at that age or even earlier) was his admission “essay”.

I know that some/many people use LLMs (ChatGPT etc) for writing (emails, docs, etc), but I’ve never found it worthwhile myself, for at least two reasons.

The mathematician Alexander Grothendieck was “considered by many to be the greatest mathematician of the twentieth century”.

Let $M_p = 2^p - 1$, so that: $$\begin{align} M_2 &= 2^2 - 1 = 4 - 1 = 3 \cr M_3 &= 2^3 - 1 = 8 - 1 = 7 \cr M_7 &= 2^7 - 1 = 128 - 1 = 127 \cr M_{127} &= 2^{127} - 1 \end{align}$$ Is $M_{127}$ prime?

This will be a quick post to collect some screenshots.

Donald Knuth has a page on his website where he sometimes posts programs he has written.

P.

My friends Suhas and Anusha have a book of excellent poems on love, translated into English from the Indian literary tradition (Sanskrit/Prakrit) across the centuries, coming out in a couple of days.1 The book itself is a delight (I’ve read a draft) and I…

The story Like every student of Sanskrit, I had always wanted to read the Vālmīki Rāmāyaṇa,1 but in the face of several distractions, this had always been a “To-do someday” item: I think I had not even fully read the mere 100 shlokas of the first sarga (S…

In December 1998, David Carlisle posted the following to comp.text.tex: \let~\catcode~`76~`A13~`F1~`j00~`P2jdefA71F~`7113jdefPALLF PA''FwPA;;FPAZZFLaLPA//71F71iPAHHFLPAzzFenPASSFthP;A$$FevP A@@FfPARR717273F737271P;ADDFRgniPAWW71FPATTFvePA**FstRsamP AGGFRr…

Here’s an arcane bit of knowledge that may be applicable sometimes: there is a tool called pkfix that can be used to improve the rendering of certain old PostScript files.

It has long been of interest to study any regularity in the prime numbers, a question which can be phrased as: “Is there a formula for the $n$th prime number?”

A quick follow-up to yesterday’s post on the “Irish logarithm” of Percy Ludgate.

Source: MJD’s blog post on “The Irish logarithm” (cites Wikipedia: Irish logarithm).

The Gaṇita-kaumudī (गणितकौमुदी) is a work on mathematics written by Nārāyaṇa Paṇḍita in 1356 CE.

A couple of years ago, someone on a mailing list asked for a proof for their observation that $$B_n = \sum_{k=1}^{n} \frac{k^n}{k!}

Harmonic series Consider the harmonic series 1+12+13+…1 + \frac12 + \frac13 + \dots1+21+31+… .

(Apologies for the rather incoherent nature of this post — I’m trying, as an experiment to push myself to post more, to “write more quickly”, so a lot of things here are not explained in a way that makes sense and some of it is even nonsensical: forget “p…

(Summary: How to add an invisible text layer to a PDF containing scanned images, using an OCR tool—in this case Google Cloud Vision API—that also gives the position of each recognized word.)

This blog post is currently a notebook on Colab (click); eventually I ought to clean it up and move it here.

This blog post is currently a notebook on Colab (click); eventually I ought to clean it up and move it here.

Sometimes, to understand what a program is doing, I’m tempted to add a log message at the start and end of every function, something like entering foo() and returning from foo().

Looks like Knuth (and sometimes others) used to run a “Programming and Problem-Solving Seminar” at Stanford.

Jon Bentley used to write a magazine column for the Communications of the ACM called “Programming Pearls” (later collected into two books).

While reading a beautiful post by Gowri Subramanya about birds, I remembered a story from one of our school textbooks, about a priest and his letter-box.

Background Following up from a previous post, I got this: This request looks like an activity that might appeal to you, @svat ji!

In a recent post, Mark Jason Dominus posed the following question: Suppose you have a bottle that contains \(N\) whole pills.

There’s a nice series of videos on YouTube, here: https://www.youtube.com/playlist?

Background One day, after a few days of managing to avoid Twitter, I logged in and happened to see these: 👆🏾@suhasm, Are you able to discern which verse it is that's illegibly rendered in the picture?

(Migrated from my older blog without any changes, as free wordpress.com blogs are infested with ads now.)