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This is a list of otherwise uncategorised papers at jdawiseman.com.
Open Mathematical Questions at jdawiseman.com
A list of the various unsolved mathematical questions that are lodged within other essays at jdawiseman.com.
Algorithm justifying that the expected value of sn/n ≈ 0.792953506407…, with C code; and The Chow & Robbins Problem: Stop at h=5 t=3.
Toss a coin at least once, stopping whenever, maximising the expected proportion of heads.
Stenier(5,6,12) cards
Proposed pack of 143 cards, being 132 Steiner cards, 10 jokers, and 1 other (#SteinerKirkmanCards).
Also see help sought on Math.StackExchange.
Trigonometry in surds, for integer multiples of 3° and of 5⅝°: Sin and Cos; Csc and Sec; Tan; and also the inner radius of n/m stars
Tournament designs
Twelve teams wish to play each other in an all-play-all format at six venues over eleven rounds. Alternatively, perhaps, in a pairs game, sixteen players wish to partner each other once (and therefore oppose each other twice) over fifteen rounds at four venues?
A Penrose Tiling: code to generate, and a PDF therefrom.
How to find one differently-weighted object from amongst (3w–3)/2 using only w weighings
There are 12 objects, identical in all respects except that one of these objects is a different weight, perhaps heavier, perhaps lighter. Determine which is the odd one out, and whether it is heavier or lighter, using only 3 weighings of an old-fashioned scale (which reports either that the left side is heavier, or that the right side is heavier, or that the two sides weigh the same).
There are 363 objects, …, using only 6 weighings, … .
There are (3w–3)/2 objects, …, using only w weighings, … (with w≥3).
2008 Olympics: who won? Comparing golds and silvers and bronzes
Proportionate Barbie (or, Barbie is not skinny)
For the same reason that a spider doesn’t look like an elephant, Barbie is not skinny. Indeed, for an adult person one foot high, Barbie is sensibly proportioned.
Computing the ISIN checksum in Excel
Given the first eleven characters, this calculates the last character, the checksum.
HTML character entities and
all unicode characters
Lists: named HTML character entities and named PostScript glyphs; and all unicode characters by number.
Web-safe colours, also in compact and HSL presentations
The back label of Quevedo Quinta Vale D’Agodinho 2008 Vintage Port
The author is mentioned.
Glasses placemat: how to avoid confusion at a port tasting
So you and your lucky guests are to enjoy a port tasting, and you will each have many glasses, one for each port.
But it is important to avoid the what-is-in-this-glass confusion, so you need a page that has a clearly labelled spot for each glass.
This PostScript program does the work.
(Short URL: www.jdawiseman.com/placemat.html.)
Big Bottles of Port: Ending The Prohibition
It used to be illegal for Port companies to sell large bottles of Port.
But the author wanted to buy an imperial of Fonseca 1985, so had the rules changed.
This essay, commissioned in late 2014, describes how.
The distillery numbers of the Scotch Malt Whisky Society
A list of the numerical codes used by the SMWS to identify distilleries.
The Arms of the Marquess of Pombal
Remastered in July 2011; available in PDF and PostScript formats.
Hexagonal Thing
A game of tactics and bidding for two players.
NHL scoring: an overtime result should be 1-0 not 2-1
A letter to the Commissioner of the National Hockey League, proposing an improvement in the scoring system.
Jet Set Willy II: A Map
A map of the classic ZX Spectrum platform game.
Queens’ Courtiers
A game of skill for two players, originally invented for Lyon Court, Queens’ College, Cambridge, but that can be played on a board.
A cheap planet-cooling machine
To cool the planet just add sulphur to a tame tethered tornado.
Passport photos of children: the Photomaton ripoff
Photomaton photo booths repeatedly fail to take valid pictures of children, much to Photomaton’s profit and the parent’s loss.
Marvel at the cunningness of the swindle; deplore the swindle.
The Solar System, to scale, for a school yard
A science lesson about the size of the solar system and its constituent cosmic bodies, all packaged and ready to use.
The Cheapest of Fukushima’s Lessons
Tepco was terrible at communicating the problems at Fukushima.
There was a complete failure to understand that corporate PR is not convincing.
Instead, nuclear power stations should have a blogger, separate from PR, to provide timely technical details.
What malformation did El Greco paint?
In many pictures the Cretan/Italian/Spanish Renaissance artist El Greco painted a head with a particular dysmorphology.
Paediatricians are asked to help diagnose the condition.
The Economist: Silver Spoons Only
Paying token wages to interns selects applicants by parental wealth.
How the UK can stop spam without damaging free speech
An outline of suggested non-extra-territorial legislation for the UK that would stop spam globally.
Non-farm payrolls: a diary
A ‘diary’, originally written for but then not wanted by, the London Review of Books, notionally about the US Employment Report (‘non-farm payrolls’), but actually about the history of financial markets.
‘Dear Aunty’, and a postscript
A letter to my Aunt, dated 7th March 1997, explaining why EMU is such a bad idea. The postscript discusses pension savings, and quotes data from the Bank of England.
How to draw the Union Jack — accurately, and Upside-Down Union Jacks
Monopoly Rents
A table with the prices and various rents of the properties on the Monopoly board.
The colours and letters and futures maturities
An explanation of the letters and colours used to identify futures maturities.
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