Math Is Fun Forum

  Discussion about math, puzzles, games and fun.   Useful symbols: ÷ × ½ √ ∞ ≠ ≤ ≥ ≈ ⇒ ± ∈ Δ θ ∴ ∑ ∫ • π ƒ -¹ ² ³ °

You are not logged in.

#326 2012-02-16 23:40:59

anonimnystefy
Real Member
From: Harlan's World
Registered: 2011-05-23
Posts: 16,049

Re: Oh,Oh,Oh,merry analysis!!!

so,does what we did has something to do with generating functions?

Last edited by anonimnystefy (2012-02-16 23:47:39)


“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.

Offline

#327 2012-02-16 23:47:34

bobbym
bumpkin
From: Bumpkinland
Registered: 2009-04-12
Posts: 109,606

Re: Oh,Oh,Oh,merry analysis!!!

Hi;

Yes, it does. That is the generating function for the postal problem with stamps of 2 cents and 3 cents. You solved a related problem a while back.


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.

Offline

#328 2012-02-16 23:48:30

anonimnystefy
Real Member
From: Harlan's World
Registered: 2011-05-23
Posts: 16,049

Re: Oh,Oh,Oh,merry analysis!!!

the e^z/(z-1)?

what was that one for?


“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.

Offline

#329 2012-02-16 23:51:51

bobbym
bumpkin
From: Bumpkinland
Registered: 2009-04-12
Posts: 109,606

Re: Oh,Oh,Oh,merry analysis!!!

Looks like the Bell numbers.


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.

Offline

#330 2012-02-17 00:22:58

anonimnystefy
Real Member
From: Harlan's World
Registered: 2011-05-23
Posts: 16,049

Re: Oh,Oh,Oh,merry analysis!!!

do you think what we did now could help us with the squares?


“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.

Offline

#331 2012-02-17 00:39:29

bobbym
bumpkin
From: Bumpkinland
Registered: 2009-04-12
Posts: 109,606

Re: Oh,Oh,Oh,merry analysis!!!

What squares?


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.

Offline

#332 2012-02-17 01:12:48

anonimnystefy
Real Member
From: Harlan's World
Registered: 2011-05-23
Posts: 16,049

Re: Oh,Oh,Oh,merry analysis!!!

in the other thread.the ones made fro the square grid of dots.


“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.

Offline

#333 2012-02-17 01:14:25

bobbym
bumpkin
From: Bumpkinland
Registered: 2009-04-12
Posts: 109,606

Re: Oh,Oh,Oh,merry analysis!!!

I remember the problem but not the particulars.


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.

Offline

#334 2012-02-17 01:18:39

anonimnystefy
Real Member
From: Harlan's World
Registered: 2011-05-23
Posts: 16,049

Re: Oh,Oh,Oh,merry analysis!!!

well just look at the thread again. smile


“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.

Offline

#335 2012-02-17 01:20:02

bobbym
bumpkin
From: Bumpkinland
Registered: 2009-04-12
Posts: 109,606

Re: Oh,Oh,Oh,merry analysis!!!

I do not know where it is.


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.

Offline

#336 2012-02-17 01:22:58

anonimnystefy
Real Member
From: Harlan's World
Registered: 2011-05-23
Posts: 16,049

Re: Oh,Oh,Oh,merry analysis!!!


“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.

Offline

#337 2012-02-17 01:25:20

bobbym
bumpkin
From: Bumpkinland
Registered: 2009-04-12
Posts: 109,606

Re: Oh,Oh,Oh,merry analysis!!!

It appears that was already worked on by a "Combinatorial Genius."


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.

Offline

#338 2012-02-17 01:27:00

anonimnystefy
Real Member
From: Harlan's World
Registered: 2011-05-23
Posts: 16,049

Re: Oh,Oh,Oh,merry analysis!!!

ok,then.but a different approach at things never hurts! big_smile


“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.

Offline

#339 2012-02-17 01:29:16

bobbym
bumpkin
From: Bumpkinland
Registered: 2009-04-12
Posts: 109,606

Re: Oh,Oh,Oh,merry analysis!!!

I think that was already done using the techniques of experimental math.


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.

Offline

#340 2012-02-17 01:36:32

anonimnystefy
Real Member
From: Harlan's World
Registered: 2011-05-23
Posts: 16,049

Re: Oh,Oh,Oh,merry analysis!!!

but is there a simpler form for that formula?


“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.

Offline

#341 2012-02-17 01:39:01

bobbym
bumpkin
From: Bumpkinland
Registered: 2009-04-12
Posts: 109,606

Re: Oh,Oh,Oh,merry analysis!!!

I do not think there is a simpler formula. There may be a simpler approximation.


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.

Offline

#342 2012-02-17 01:52:52

anonimnystefy
Real Member
From: Harlan's World
Registered: 2011-05-23
Posts: 16,049

Re: Oh,Oh,Oh,merry analysis!!!

i don't need an approximation.but i know there is a simpler formula.

i need it for this programming problem which is supposed to be O(1):

Task :: Kvadratici
In planar rectangular integer grid dimension n x m (are nm squares). How many different squares are in this grid which have corners on integer coordinate (sides of this squares doesn't have to be parallel with sides of grid) ?


INPUT:
In first and only row of standard input are two numbers n and m - dimension of rectangular grid (1 <= n, m <= 10^9).


OUTPUT:
Let K be needed number of squares. On standard input write modulo with division K with 10^9 + 7.



Notes:
In 40% tests 1 <= n, m <= 100
In 60% tests 1 <= n, m <= 1.000
In 80% tests 1 <= n, m <= 1.000.000



Input:
2 3

Output:
10




Input:
500 501

Output:
271062715


“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.

Offline

#343 2012-02-17 01:54:43

bobbym
bumpkin
From: Bumpkinland
Registered: 2009-04-12
Posts: 109,606

Re: Oh,Oh,Oh,merry analysis!!!

Why not continue with that in the other 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.

Offline

#344 2012-02-17 01:56:59

anonimnystefy
Real Member
From: Harlan's World
Registered: 2011-05-23
Posts: 16,049

Re: Oh,Oh,Oh,merry analysis!!!

let's. smile

i will post it there.


“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.

Offline

#345 2012-02-17 02:04:57

bobbym
bumpkin
From: Bumpkinland
Registered: 2009-04-12
Posts: 109,606

Re: Oh,Oh,Oh,merry analysis!!!

Coefficient of x^10000?


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.

Offline

#346 2012-02-17 02:08:33

anonimnystefy
Real Member
From: Harlan's World
Registered: 2011-05-23
Posts: 16,049

Re: Oh,Oh,Oh,merry analysis!!!

hi bobbym

the smallest singularity is at (sqrt(5)-1)/2 and when we expand there we get the principal part:

Last edited by anonimnystefy (2012-02-17 02:08:42)


“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.

Offline

#347 2012-02-17 02:17:23

bobbym
bumpkin
From: Bumpkinland
Registered: 2009-04-12
Posts: 109,606

Re: Oh,Oh,Oh,merry analysis!!!

I am not getting that.


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.

Offline

#348 2012-02-17 02:23:12

anonimnystefy
Real Member
From: Harlan's World
Registered: 2011-05-23
Posts: 16,049

Re: Oh,Oh,Oh,merry analysis!!!

what did you get?


“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.

Offline

#349 2012-02-17 02:24:56

bobbym
bumpkin
From: Bumpkinland
Registered: 2009-04-12
Posts: 109,606

Re: Oh,Oh,Oh,merry analysis!!!


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.

Offline

#350 2012-02-17 02:27:53

anonimnystefy
Real Member
From: Harlan's World
Registered: 2011-05-23
Posts: 16,049

Re: Oh,Oh,Oh,merry analysis!!!

hi bobbym

i forgot to multiply by (sqrt(5)-1)/2


“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.

Offline

Board footer

Powered by FluxBB