Math Is Fun Forum

jacks

Member

Registered: 2012-11-21

Posts: 132

positive integer ordered pairs (n,r)

{A} Total no. of positive integer ordered pairs of

which satisfy

{B} Total no. of positive integer ordered pairs of

which satisfy

bobbym

bumpkin

From: Bumpkinland

Registered: 2009-04-12

Posts: 109,606

Re: positive integer ordered pairs (n,r)

Hi;

There are 6 ways for 120 and 2 ways for 2013.

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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.

jacks

Member

Registered: 2012-11-21

Posts: 132

Re: positive integer ordered pairs (n,r)

Thanks Bobbym would you like to explain it to me, Thanks

bobbym

bumpkin

From: Bumpkinland

Registered: 2009-04-12

Posts: 109,606

Re: positive integer ordered pairs (n,r)

Hi;

As far as I know there is no known formula for these problems. The latest work only provides a bound, not an exact answer. These had to be computed for both 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.

jacks

Member

Registered: 2012-11-21

Posts: 132

Re: positive integer ordered pairs (n,r)

Yes Bobbym I need upper bond.

bobbym

bumpkin

From: Bumpkinland

Registered: 2009-04-12

Posts: 109,606

Re: positive integer ordered pairs (n,r)

Hi;

Unless I am misunderstanding their paper they have only established an upper bound for

n >= 2r

this is almost useless for your question.

---

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.