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Richard Walker

New Year Problem - Solution

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For the problem see

https://learn1.open.ac.uk/mod/oublog/viewpost.php?post=242384


This was new to me. I found it in Mathematical Puzzles: A Connoisseur’s Collection, by Peter Winkler.

Think of the 2023 numbers 1, 11, 111, 1111, … up to the number with 2023 digits, all 1’s. Imagine dividing each by 2022 and taking the remainder. There are only 2022 distinct remainders possible 0, 1, 2, 3, … 2021 but we have produced 2023 remainders, and thus there must be at least two of the numbers 1, 11, 111, 1111, … with the same remainder.

If we now take the smaller of the two from the larger, the number we get must be divisible by 2022, and it will consist only of 0’s and 1’s .as required.

It’s late, hope I have the details right, but you should be able to see that the argument is correct and 2022 could be replaced by any number we please.

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Richard Walker

New Year Problem

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Show we can find a multiple of 2022 whose digits are all 0’s and 1’s.

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Richard Walker

Dad Joke

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I met this bloke who claimed he’d built a house with a thousand floors. I thought, that’s a tall story.

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Richard Walker

Robin

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Whenever I go on the garden the robin appears. It will come to the feeder while I am standing really close, a foot or so, and I'm hoping I can get it to take food out of my hand.




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Richard Walker

My Viral Livestock

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This surprises me!

I calculate that if all the viral particles in my garden were arranged end-to-end they would reach to the Sun.

It's estimated that each cm3 of soil contains 1011 such particles, of multifarious kinds, some known to science, most not. A typical diameter for a virus particle is 10-7 m. 

So the particles in each cm3 would stretch for 1011 x 10-7 m = 104 m = 10 km.

I estimate the volume of topsoil in my garden as a bit over 15 m3, and 1 m3 = 106 cm3.

That gives a distance of 15 x 106 x 10 km = 150 million km, the distance from here to the Sun. 

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Richard Walker

Fluorescent Tonic

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It's little surprise that day-glo items like highlighter pens fluoresce under Ultraviolet but who would have guessed that Indian Tonic Water is also fluorescent? It's the quinine in it that causes the fluoresence.




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Richard Walker

Uranium glass flourescing - See earlier post

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Richard Walker

Cookery Musings

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Edited by Richard Walker, Tuesday, 28 Dec 2021, 20:53

When people compliment me

On my Indian cuisine

Are they just

Trying to curry flavour?

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Richard Walker

Radioactive Glass

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Edited by Richard Walker, Wednesday, 29 Dec 2021, 21:54

I rediscovered this goblet at the back of a shelf. It’s something I picked up in an antique shop years ago.


I bought it for its attractive colour and grape vine design. Looking at it anew it occurred to me that it’s probably uranium glass, which has literally got uranium in it, although not very much, a few percent at most, and although it will be slightly radioactive it ought to be harmless. Uranium glass used to be quite popular but fell out of favour, possibly because the availability of uranium was restricted during the Cold War (Wikipedia).

If it is uranium glass it should fluoresce under ultraviolet, so I got a UV lamp and tried it. Wow!!! How beautiful is this? I was so excited.





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Richard Walker

Word of the day - Thigmotaxis

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The tendency of an animal to hug vertical surfaces, especially in a situation of anxiety or potential danger.

I came across this word when reading about house mice, but many kinds of animal exhibit this behaviour. I think we do; if I were exploring an unfamiliar open field with boundary hedges I’d probably follow the perimeter at first, even without any overhead threat.

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Richard Walker

I Stumbled Across This Beautiful Wayside Decoration

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Edited by Richard Walker, Saturday, 25 Dec 2021, 16:02


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Richard Walker

Word of the day - Nugget

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Edited by Richard Walker, Monday, 20 Dec 2021, 01:29

A small nug. Not joking; seems a nug is a dialect word for a chunk of something; and there you have it. Pure gold, I love words.

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Richard Walker

Ant Joke

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Exuberant = ant no longer driving taxi

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Richard Walker

Steamrollers

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Don’t see the point of them.
Why would you want to roll steam?
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Richard Walker

What do you call?

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What do you call a woman that swears at tea? Kirsty.

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Richard Walker

Word of the day- lollapalooza

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lollapalooza - something extraordinarily impressive, similar to a humdinger.

Attested from the 1890s but the origin is unknown; it could be a made-up word. New to me, it was in a book I’m reading. Though I’d never seen it before, the context made it clear at once what it meant, and I’ve learned a new word. Language is so productive, it’s possible to invent words that speakers will instantly grasp and start using.
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Richard Walker

Blower

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Edited by Richard Walker, Thursday, 16 Dec 2021, 16:12

After seeing a YouTube video "hoes this app blow out candles" about an app called 'Blower' on The Action Lab I bought a copy to try it out.

The app is a simulation of a fan and the amazing thing is that it does actually blow things about. The Action Lab showed it really ould blow out a small candle but I just tried blowing some small scraps of paper and sure enough they move.

It's quite surprising and some of tne explanations suggested, "It's vibration" and so on, don't account for it. The Action Lab explains what's going on quite well.







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Richard Walker

Dad Dog Joke

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Having trouble with a noisy dog? Call our Yelpline 24/7

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Richard Walker

If Christmas lasted all year

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A popular question in Christmas quizzes asks how many gifts were sent, and received, altogether in the carol The Twelve Days of Christmas.

So on day 1 (sing the song) it was 1

On day 2 (sing the song) it was 2 plus 1 = 3

On day 3 plus 2 plus 1 = 6

….

What is the total after 12 days: 1 plus 3 plus 6 …?

Now, what if there were 365 days of Christmas? What would the grand total be then?


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Richard Walker

Knock-knock!

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Who's there?

No it’s Fred.

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Richard Walker

Dawn Haiku

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Edited by Richard Walker, Tuesday, 14 Dec 2021, 00:17
Winter sunrise
Spreads across the courtyard.
Another day.
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Richard Walker

On the Surprising Similarity of Large Shopping Centres

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If you’ve seen one large shopping centre, you’ve seen a mall.

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Richard Walker

Dawn 11 December 2021

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Richard Walker

Christmas market at Stratford

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Yesterday we went to the Christmas Market at Stratford-on-Avon. A very interesting town, with many beautiful old houses, including one that belonged to Shakespeare's father John and is very likely to have been the playwright's birthplace. As we were leaving just at sunset the lights were coming on and the scene was almost magical.


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Richard Walker

Horsey horsey

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My friend was rushed to hospital after being kicked by a horse. Luckily his condition is stable.

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