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#1 2012-01-20 01:38:43

juantheron
Member
Registered: 2011-10-19
Posts: 312

sum of digit

Let

.Consider all positive differences of elements of
.

If

is the Sum of all these differences,find the Sum of the digits of

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#2 2012-01-20 04:52:52

phrontister
Real Member
From: The Land of Tomorrow
Registered: 2009-07-12
Posts: 4,818

Re: sum of digit

Hi juantheron,

Last edited by phrontister (2012-01-23 14:13:36)


"The good news about computers is that they do what you tell them to do. The bad news is that they do what you tell them to do." - Ted Nelson

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#3 2012-01-20 05:12:26

TheDude
Member
Registered: 2007-10-23
Posts: 361

Re: sum of digit

I get the same answer.


Wrap it in bacon

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#4 2012-01-20 06:21:27

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

Re: sum of digit

Hi;


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.

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#5 2012-01-20 07:38:52

juantheron
Member
Registered: 2011-10-19
Posts: 312

Re: sum of digit

Thanks phrontister Dude, Bobbym.

actually I have mistake it to Write The Question.

and actual Question is

Let

.Consider all positive differences of elements of S.If M is the sum of all these differences,find the sum of the digits of M?

Thanks

Last edited by juantheron (2012-01-20 07:39:57)

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#6 2012-01-20 08:22:47

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

Re: sum of digit

Hi juantheron;


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.

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#7 2012-01-20 17:59:44

phrontister
Real Member
From: The Land of Tomorrow
Registered: 2009-07-12
Posts: 4,818

Re: sum of digit

Hi juantheron,

I got the same answer as Bobby.

Last edited by phrontister (2012-01-23 14:14:36)


"The good news about computers is that they do what you tell them to do. The bad news is that they do what you tell them to do." - Ted Nelson

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#8 2012-01-21 00:04:39

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

Re: sum of digit

Hi phrontister;

I got the same answer as Bobby.

Usually about 75% of my answers agree with this Bobby chap too! On a good day, more!


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.

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#9 2012-01-21 01:34:04

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

Re: sum of digit

hi bobbym

i would say 100% not 75%.great minds think alike.


“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.

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#10 2012-01-21 01:46:27

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

Re: sum of digit

Just rechecked my calculations and you are right it is 100%.


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.

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#11 2012-01-21 01:54:17

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

Re: sum of digit

hi bobbym

how are you today?


“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.

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#12 2012-01-21 02:07:04

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

Re: sum of digit

Hi;

I am okay, watched an old movie.


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.

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#13 2012-01-21 02:24:41

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

Re: sum of digit

which one?


“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.

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#14 2012-01-21 02:28:11

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

Re: sum of digit

"World Without End." A real killer.


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.

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#15 2012-01-21 04:05:41

juantheron
Member
Registered: 2011-10-19
Posts: 312

Re: sum of digit

Thanks bobbym and phrontister

bobbym i want explanation for how can i get the linear recursive function

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#16 2012-01-21 05:03:38

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

Re: sum of digit

Hi juantheron;

Post#1 and #2 provide 2 ways to solve the problem, You can consider my way as some empirical evidence. The binomial was derived by playing spot the pattern, a fairly common technique in combinatorics. At least the way I do it.


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.

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