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#26 2014-09-22 01:43:28
- ElainaVW
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- Registered: 2013-04-29
- Posts: 580
Re: Bitter snails
Check the coefficient of x^15 and multiply by 15![/hide]
Last edited by ElainaVW (2014-09-22 01:44:40)
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#27 2014-09-22 01:50:10
- anonimnystefy
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- From: Harlan's World
- Registered: 2011-05-23
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Re: Bitter snails
Hi
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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#28 2014-09-22 01:53:08
- bobbym
- bumpkin
- From: Bumpkinland
- Registered: 2009-04-12
- Posts: 109,606
Re: Bitter snails
Hi;
If you are looking for a closed form you might start with the gf and for that post #26 looks about right.
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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#29 2014-09-22 01:55:00
- anonimnystefy
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- From: Harlan's World
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Re: Bitter snails
Hm, I had that GF at one point, but was not sure if it would work.
What is a gAr type answer?
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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#30 2014-09-22 01:59:56
- bobbym
- bumpkin
- From: Bumpkinland
- Registered: 2009-04-12
- Posts: 109,606
Re: Bitter snails
See post #22 method 1.
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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#31 2014-09-22 02:01:55
- anonimnystefy
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- From: Harlan's World
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Re: Bitter snails
So, an answer in form of a recurrence?
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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#32 2014-09-22 02:03:37
- bobbym
- bumpkin
- From: Bumpkinland
- Registered: 2009-04-12
- Posts: 109,606
Re: Bitter snails
Not necessarily, just one I do not understand.
Hm, I had that GF at one point, but was not sure if it would work.
Please correct that statement.
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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#33 2014-09-22 02:09:26
- anonimnystefy
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- From: Harlan's World
- Registered: 2011-05-23
- Posts: 16,049
Re: Bitter snails
Correct it? Why?
Why do you not understand the recurrence?
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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#34 2014-09-22 02:13:54
- bobbym
- bumpkin
- From: Bumpkinland
- Registered: 2009-04-12
- Posts: 109,606
Re: Bitter snails
Correct it? Why?
Because you could have easily expanded it and checked, that is the beauty of EM. You have verification that you are right...
Why do you not understand the recurrence?
In the battle for Brooklyn I was severely wounded when a mortar shell grazed my head. I lost 4 ounces of high grade brain ooze. I guess it was the portion that controlled double indexed recurrences.
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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#35 2014-09-22 02:22:00
- anonimnystefy
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- From: Harlan's World
- Registered: 2011-05-23
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Re: Bitter snails
I had nothing to check it against. I did not have another solution.
The recurrence is not hard at all.
You look at what happens when you bring in another snail. You can either put it in a group with other snails or put it in a group of its own.
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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#36 2014-09-22 02:25:21
- bobbym
- bumpkin
- From: Bumpkinland
- Registered: 2009-04-12
- Posts: 109,606
Re: Bitter snails
I had nothing to check it against. I did not have another solution.
And after you had two solutions?
You look at what happens when you bring in another snail. You can either put it in a group with other snails or put it in a group of its own.
That kind of reasoning went out in the 4 ounces of brain ooze. Did you run the recurrence, that I can understand.
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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#37 2014-09-22 02:29:09
- anonimnystefy
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- From: Harlan's World
- Registered: 2011-05-23
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Re: Bitter snails
After I had the two solutions I did not go back to check it.
Yes, I did run 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.
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#38 2014-09-22 02:29:50
- bobbym
- bumpkin
- From: Bumpkinland
- Registered: 2009-04-12
- Posts: 109,606
Re: Bitter snails
How? I never get them to work in 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.
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#39 2014-09-22 02:31:42
- anonimnystefy
- Real Member
- From: Harlan's World
- Registered: 2011-05-23
- Posts: 16,049
Re: Bitter snails
Hi
a[1, 1] = 1;
a[1, k_] := 0;
a[n_, 1] := 1;
a[n_, k_] := k (a[n - 1, k - 1] + a[n - 1, k]);
a[15, 4]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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#40 2014-09-22 02:34:33
- bobbym
- bumpkin
- From: Bumpkinland
- Registered: 2009-04-12
- Posts: 109,606
Re: Bitter snails
Can you use the built in command RecurrenceTable?
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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#41 2014-09-22 02:36:17
- anonimnystefy
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- From: Harlan's World
- Registered: 2011-05-23
- Posts: 16,049
Re: Bitter snails
Won't it just take longer?
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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#42 2014-09-22 02:37:16
- bobbym
- bumpkin
- From: Bumpkinland
- Registered: 2009-04-12
- Posts: 109,606
Re: Bitter snails
Longer to run? I doubt it, built in commands are usually faster.
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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#43 2014-09-22 03:04:53
- anonimnystefy
- Real Member
- From: Harlan's World
- Registered: 2011-05-23
- Posts: 16,049
Re: Bitter snails
Either way, I do not see a reason to use that command here.
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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#44 2014-09-22 03:11:57
- bobbym
- bumpkin
- From: Bumpkinland
- Registered: 2009-04-12
- Posts: 109,606
Re: Bitter snails
The question I am asking is do you know how to get the built in one working for this example?
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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#45 2014-09-22 03:12:26
Re: Bitter snails
No, it is redundant.
'And fun? If maths is fun, then getting a tooth extraction is fun. A viral infection is fun. Rabies shots are fun.'
'God exists because Mathematics is consistent, and the devil exists because we cannot prove it'
I'm not crazy, my mother had me tested.
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#46 2014-09-22 03:14:58
- bobbym
- bumpkin
- From: Bumpkinland
- Registered: 2009-04-12
- Posts: 109,606
Re: Bitter snails
Not necessarilly, it uses memoization so for very large arguments it will be much faster.
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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#47 2014-09-22 03:44:04
Re: Bitter snails
How do I get the recurrence formula for this problem?
'And fun? If maths is fun, then getting a tooth extraction is fun. A viral infection is fun. Rabies shots are fun.'
'God exists because Mathematics is consistent, and the devil exists because we cannot prove it'
I'm not crazy, my mother had me tested.
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#48 2014-09-22 03:51:54
- anonimnystefy
- Real Member
- From: Harlan's World
- Registered: 2011-05-23
- Posts: 16,049
Re: Bitter snails
You look at what happens when you bring in another snail. You can either put it in a group with other snails or put it in a group of its own.
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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#49 2014-09-22 13:21:21
Re: Bitter snails
What are n,k?
'And fun? If maths is fun, then getting a tooth extraction is fun. A viral infection is fun. Rabies shots are fun.'
'God exists because Mathematics is consistent, and the devil exists because we cannot prove it'
I'm not crazy, my mother had me tested.
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#50 2014-09-23 00:45:34
- anonimnystefy
- Real Member
- From: Harlan's World
- Registered: 2011-05-23
- Posts: 16,049
Re: Bitter snails
n is the number of snails, k the number of people.
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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