Math Is Fun Forum

bobbym

bumpkin

From: Bumpkinland

Registered: 2009-04-12

Posts: 109,606

Re: Prime sum of three term arithmetic progression?

That is going to be true regardless of whatever fifth term he puts there.

What is the next term in the sequence

1, 2, 4, 8, 16...?

---

In mathematics, you don't understand things. You just get used to them.
If it ain't broke, fix it until it is.
Always satisfy the Prime Directive of getting the right answer above all else.

anonimnystefy

Real Member

From: Harlan's World

Registered: 2011-05-23

Posts: 16,049

Re: Prime sum of three term arithmetic progression?

Well, it is, but it is the most likely that the 6th term they want is 3/16.

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“Here lies the reader who will never open this book. He is forever dead.
“Taking a new step, uttering a new word, is what people fear most.” ― Fyodor Dostoyevsky, Crime and Punishment
The knowledge of some things as a function of age is a delta function.

bobbym

bumpkin

From: Bumpkinland

Registered: 2009-04-12

Posts: 109,606

Re: Prime sum of three term arithmetic progression?

Why do you like 3 / 16?

---

In mathematics, you don't understand things. You just get used to them.
If it ain't broke, fix it until it is.
Always satisfy the Prime Directive of getting the right answer above all else.

anonimnystefy

Real Member

From: Harlan's World

Registered: 2011-05-23

Posts: 16,049

Re: Prime sum of three term arithmetic progression?

I do not. It just looks like something that the question setter might like.

---

“Here lies the reader who will never open this book. He is forever dead.
“Taking a new step, uttering a new word, is what people fear most.” ― Fyodor Dostoyevsky, Crime and Punishment
The knowledge of some things as a function of age is a delta function.

bobbym

bumpkin

From: Bumpkinland

Registered: 2009-04-12

Posts: 109,606

Re: Prime sum of three term arithmetic progression?

In what manner do you arrive at it?

By the way do you know about the demonstrations?

---

In mathematics, you don't understand things. You just get used to them.
If it ain't broke, fix it until it is.
Always satisfy the Prime Directive of getting the right answer above all else.

anonimnystefy

Real Member

From: Harlan's World

Registered: 2011-05-23

Posts: 16,049

Re: Prime sum of three term arithmetic progression?

I noticed that the numerator of the terms with odd indexes are the same as their indexes, and the ones with even indexes were 1, so, I tried multiplying both the denominator and the numerator of those by the required power of 2. After that it was easy.

What demonstrations?

---

“Here lies the reader who will never open this book. He is forever dead.
“Taking a new step, uttering a new word, is what people fear most.” ― Fyodor Dostoyevsky, Crime and Punishment
The knowledge of some things as a function of age is a delta function.

bobbym

bumpkin

From: Bumpkinland

Registered: 2009-04-12

Posts: 109,606

Re: Prime sum of three term arithmetic progression?

Wolfram of course! They have thousands of them.

http://demonstrations.wolfram.com/

Pick a topic and look around.

---

In mathematics, you don't understand things. You just get used to them.
If it ain't broke, fix it until it is.
Always satisfy the Prime Directive of getting the right answer above all else.

anonimnystefy

Real Member

From: Harlan's World

Registered: 2011-05-23

Posts: 16,049

Re: Prime sum of three term arithmetic progression?

Is there a way to make this in M?

---

“Here lies the reader who will never open this book. He is forever dead.
“Taking a new step, uttering a new word, is what people fear most.” ― Fyodor Dostoyevsky, Crime and Punishment
The knowledge of some things as a function of age is a delta function.

bobbym

bumpkin

From: Bumpkinland

Registered: 2009-04-12

Posts: 109,606

Re: Prime sum of three term arithmetic progression?

Why not just download the notebook?

---

In mathematics, you don't understand things. You just get used to them.
If it ain't broke, fix it until it is.
Always satisfy the Prime Directive of getting the right answer above all else.

anonimnystefy

Real Member

From: Harlan's World

Registered: 2011-05-23

Posts: 16,049

Re: Prime sum of three term arithmetic progression?

I have. There is no code in it.

---

“Here lies the reader who will never open this book. He is forever dead.
“Taking a new step, uttering a new word, is what people fear most.” ― Fyodor Dostoyevsky, Crime and Punishment
The knowledge of some things as a function of age is a delta function.

bobbym

bumpkin

From: Bumpkinland

Registered: 2009-04-12

Posts: 109,606

Re: Prime sum of three term arithmetic progression?

Hi;

There is code in there.

---

In mathematics, you don't understand things. You just get used to them.
If it ain't broke, fix it until it is.
Always satisfy the Prime Directive of getting the right answer above all else.

anonimnystefy

Real Member

From: Harlan's World

Registered: 2011-05-23

Posts: 16,049

Re: Prime sum of three term arithmetic progression?

That is an animation. I cannot see any actual M code.

---

“Here lies the reader who will never open this book. He is forever dead.
“Taking a new step, uttering a new word, is what people fear most.” ― Fyodor Dostoyevsky, Crime and Punishment
The knowledge of some things as a function of age is a delta function.

bobbym

bumpkin

From: Bumpkinland

Registered: 2009-04-12

Posts: 109,606

Re: Prime sum of three term arithmetic progression?

On the sides are cell grouping lines click them and you see some code.

But that is an authored version. The code is incomplete, I have another source notebook.

---

In mathematics, you don't understand things. You just get used to them.
If it ain't broke, fix it until it is.
Always satisfy the Prime Directive of getting the right answer above all else.

bobbym

bumpkin

From: Bumpkinland

Registered: 2009-04-12

Posts: 109,606

Re: Prime sum of three term arithmetic progression?

Try here for the source code.

http://demonstrations.wolfram.com/versi … rsion=0026

If you can not get that then here is what you want:

Manipulate[
 Module[{m1 = {Reverse[pt1], {-1, 1} pt1}, 
   m2 = {Reverse[pt2], {-1, 1} pt2}}, 
  Graphics[MapIndexed[{Thickness[0.01 th^#2[[1]]], Line[#]} &, 
    NestList[
     Flatten[Map[{{#[[2]], #[[2]] + m1.(#[[2]] - #[[1]])}, {#[[
            2]], #[[2]] + m2.(#[[2]] - #[[1]])}} &, #], 
       1] &, {{{0, -1}, {0, 0}}}, gen]], 
   PlotRange -> {{-3, 3}, {-1, 5}}, ImageSize -> {500, 400}]], {{gen, 
   7, "generations"}, 3, 10, 1}, {{th, 0.7, "thickness ratio"}, 0.01, 
  1.2}, {{pt1, {-0.25, 0.75}}, {-3, -1}, {3, 3}, 
  Locator}, {{pt2, {0.25, 0.75}}, {-3, -1}, {3, 3}, Locator}]

---

In mathematics, you don't understand things. You just get used to them.
If it ain't broke, fix it until it is.
Always satisfy the Prime Directive of getting the right answer above all else.

anonimnystefy

Real Member

From: Harlan's World

Registered: 2011-05-23

Posts: 16,049

Re: Prime sum of three term arithmetic progression?

Actually, you were right. When I clicked on an unexpanded cell, the code was shown.

---

“Here lies the reader who will never open this book. He is forever dead.
“Taking a new step, uttering a new word, is what people fear most.” ― Fyodor Dostoyevsky, Crime and Punishment
The knowledge of some things as a function of age is a delta function.

bobbym

bumpkin

From: Bumpkinland

Registered: 2009-04-12

Posts: 109,606

Re: Prime sum of three term arithmetic progression?

I have provided the code for you in the previous post. Cell grouping is a way to hide many cells. They appear as one. Also, it is a way to arrange work together.

Nothing beats M.

---

In mathematics, you don't understand things. You just get used to them.
If it ain't broke, fix it until it is.
Always satisfy the Prime Directive of getting the right answer above all else.

anonimnystefy

Real Member

From: Harlan's World

Registered: 2011-05-23

Posts: 16,049

Re: Prime sum of three term arithmetic progression?

Thanks, anyway.

I am going to look at some more of them.

---

“Here lies the reader who will never open this book. He is forever dead.
“Taking a new step, uttering a new word, is what people fear most.” ― Fyodor Dostoyevsky, Crime and Punishment
The knowledge of some things as a function of age is a delta function.

bobbym

bumpkin

From: Bumpkinland

Registered: 2009-04-12

Posts: 109,606

Re: Prime sum of three term arithmetic progression?

That is why I sent you the link. There are thousands with dozens coming in everyday. Did you drag on the branches as well as move the slider? What other language other than a CAS could program that in 5 lines of code?

---

In mathematics, you don't understand things. You just get used to them.
If it ain't broke, fix it until it is.
Always satisfy the Prime Directive of getting the right answer above all else.

anonimnystefy

Real Member

From: Harlan's World

Registered: 2011-05-23

Posts: 16,049

Re: Prime sum of three term arithmetic progression?

Yes, I have moved them. I will try and change their code to get the tree from one of the eulerproject problems.

Oh, have you seen my solution of phro's "bobbym's YOB" puzzle?

Last edited by anonimnystefy (2013-05-08 09:09:17)

---

“Here lies the reader who will never open this book. He is forever dead.
“Taking a new step, uttering a new word, is what people fear most.” ― Fyodor Dostoyevsky, Crime and Punishment
The knowledge of some things as a function of age is a delta function.

bobbym

bumpkin

From: Bumpkinland

Registered: 2009-04-12

Posts: 109,606

Re: Prime sum of three term arithmetic progression?

I worked on that one for Agnishom and solved it.

No, I have not seen your solution. I have been busy working on a full solution to the sudoku thread.

---

In mathematics, you don't understand things. You just get used to them.
If it ain't broke, fix it until it is.
Always satisfy the Prime Directive of getting the right answer above all else.

anonimnystefy

Real Member

From: Harlan's World

Registered: 2011-05-23

Posts: 16,049

Re: Prime sum of three term arithmetic progression?

I do not remember your solution.

Sudoku thread?

---

“Here lies the reader who will never open this book. He is forever dead.
“Taking a new step, uttering a new word, is what people fear most.” ― Fyodor Dostoyevsky, Crime and Punishment
The knowledge of some things as a function of age is a delta function.

bobbym

bumpkin

From: Bumpkinland

Registered: 2009-04-12

Posts: 109,606

Re: Prime sum of three term arithmetic progression?

It might not be the same problem but I worked on a projecteuler problem. I think it was #300? It should have me on the solution list.

Yes, the one you and phrontister are working on. There are two questions that need answering.

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In mathematics, you don't understand things. You just get used to them.
If it ain't broke, fix it until it is.
Always satisfy the Prime Directive of getting the right answer above all else.

anonimnystefy

Real Member

From: Harlan's World

Registered: 2011-05-23

Posts: 16,049

Re: Prime sum of three term arithmetic progression?

I do not remember working on a sudoku problem...

---

“Here lies the reader who will never open this book. He is forever dead.
“Taking a new step, uttering a new word, is what people fear most.” ― Fyodor Dostoyevsky, Crime and Punishment
The knowledge of some things as a function of age is a delta function.

bobbym

bumpkin

From: Bumpkinland

Registered: 2009-04-12

Posts: 109,606

Re: Prime sum of three term arithmetic progression?

It is sort of a combination of sudoku and a rubiks cube.

---

In mathematics, you don't understand things. You just get used to them.
If it ain't broke, fix it until it is.
Always satisfy the Prime Directive of getting the right answer above all else.

anonimnystefy

Real Member

From: Harlan's World

Registered: 2011-05-23

Posts: 16,049

Re: Prime sum of three term arithmetic progression?

Oh, that one. Well, I haven't worked on it much.

---

“Here lies the reader who will never open this book. He is forever dead.
“Taking a new step, uttering a new word, is what people fear most.” ― Fyodor Dostoyevsky, Crime and Punishment
The knowledge of some things as a function of age is a delta function.