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#proof

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I HEREBY SHEW PROOF THAT I CAN PLAY "EASY MUSIC" AND SING N'AT, AND SIMULTANEOUSLY ANNOUNCE, NAY, DEMONSTRATE WHAT I'VE BEEN DOING TO THIS HYMN FOR, HEH, QUITE SOME TIME NOW! WHO KNOWS HOW LONG ITLL TAKE TO FINE TUNE!? TEN YEARS!? ELEVEN!?
MWAHAHAHAHAHAHAHAH!!!
youtu.be/5hxgi8hnRBk

youtu.be- YouTubeEnjoy the videos and music you love, upload original content, and share it all with friends, family, and the world on YouTube.

Proof by starvation: This is a proof form in which you first prove that a counterexample to the theorem must have property X, then, using X, prove that it must also have property Y, then that it must also have property Z, ... until you have piled up so many requirements on a counterexample that everybody sees that it cannot exist.

I have done that a few times. It is a nice way to organize one's thoughts.

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@BernhardWerner My favorite alternative #proof strategy for #induction proofs are #combinatorial (counting) proofs.

I suppose the standard example might be the proof of the coefficients in the binomial theorem expansion, or for the sum of binomial coefficients being powers of 2. These can be proved by induction, of course, but I'm not sure that's common given how easier it is to do a counting proof. It is also much clearer and avoids tedious algebra.

One I like is proving that the sum 1 + 2 + 3 + ⋯ + 𝑛 is 𝑛 + 1 choose 2, the binomial coefficient \(\binom{n+1}{2}\). Bijection proof, counts the same thing in two ways. The thing being counted is the number of ways of choosing two things (distinct, without repetition) from the set {0, 1, ..., 𝑛}. By definition, it is the binomial coefficient we want. The other way to count is to fix the larger number 𝑘, the remaining choices are any of the 𝑘 numbers from 0 to 𝑘 - 1. Thus, across all possible larger numbers, we get the sum from 1 to n.

An alternative alternate proof of the same, slightly more geometric is as follows: arrange dots in a triangle, 1 on row 1, 2 on row 2, and so on up to row n, with n dots. Add a phantom row of n+1 dots below. We want to add up all dots in first n rows: ∑ 𝑖. If you think of all of this as a binary tree/DAG, then every dot has two children (imagine Pascal's triangle). If you pick any two dots in the phantom row, their common ancestor is unique. So counting dots is same as picking two dots in phantom row. Which is the binomial coefficient we want.

Benjamin and Quinn's book on combinatorial proofs is amazing for interpretations of this form (I learned the first proof from it). See also: en.wikipedia.org/wiki/Combinat

en.wikipedia.orgCombinatorial proof - Wikipedia

and , and every nation in the , should now insist on proof of vaccination against all generally preventable diseases from Americans prior to entry into their country.

If you want Bobby Brainworm in charge of your public health, it's your funeral, but you don't get to spread those germs in our countries to those of our citizens that are too vulnerable to be immunized.

Flag down on the play, B&H Photo-Video! Was repeatedly assured in-store that buying items & having them shipped would not incur any charges (I bought $200 of stuff!). So when it shipped & I saw a shipping charge, I called right away. Not like them, they're usually more honest.
#BandH #Photo #Video #Store #free #shipping #not #really #called for #credit #back #filter #holder #effects #photography #pictures #instant #color #black& #white #negatives #proof #sheet #roll #film #bellows #camera #shoot

Here's a bit of how I #work .

I make my patterns myself - the ones I use to cut out pieces for #leather #goods and the ones I use for a #handcarved #decoration .

Two of these #leather #belts are decorated by a pattern that are inspired by #Estonian #folkart .

The other two are decorated by a sort of pattern that makes them #unique as they're cut onto the leather without any prepared drawing.

So as there is no #written #proof of the making process - are they #real or are they #myth ?

inspired by tavis' deep field #nebulabrot #DeepZoom images on #fractal #fractals forums, I did a little shader that for each c in the complement of the #MandelbrotSet M, colours according to how often z <- z^2 + c hits a given small target disc , weighted by derivative (as a proxy for point density).

it looks as though the hit sources are distributed everywhere near the boundary of M, which i think i can prove for target discs outside a sufficiently large esape circle, but i'm not sure how for discs nearer M. intuitively, by the time any cell pair in binary decomposition of exterior escapes, it covers an annulus with radii R, R^2, so any disc outside R will be hit by some region in every cell pair.

#math#maths#proof