Everything posted by Genady
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Why are two answers different using the two equivalent formulas in combinatorics ?
In the eq (1) here your upper limit of summation is k=r. Are you sure about it? I don't think it is correct. The case (2) doesn't make sense. You cannot distribute 2 objects in 3 cells such that there are no empty cells. I think, you have to have at least as many objects as there are cells for these formulas to make sense. That's why I think that the upper limit of summation in eq (1) is incorrect. Did you derive the eq (1) by a combinatorial argument, as requested?
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Why are two answers different using the two equivalent formulas in combinatorics ?
You can substitute A(r-k, n) in eq.(1) using the right side of eq.(2) while instead of (n-v)r you should put (n-v)r-k. Let's see what you get.
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War Games: Russia Takes Ukraine, China Takes Taiwan. US Response?
There are universities and academic institutions in Ukraine. They conduct scientific research, including that in biology. Here is a list of Biology in Ukraine: 31 Best universities Ranked 2021 (edurank.org)
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Why are two answers different using the two equivalent formulas in combinatorics ?
Yes, this formula is correct. However, the equation (2) is not. Take for example r=2 objects and n=2 cells. There is only 1 way to distribute them with no empty cells, i.e. 1+1. But the equation (2) gives 2. This would be so if, for example, the objects were distinguishable.
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Why are two answers different using the two equivalent formulas in combinatorics ?
OK. Now, the first formula in the OP says, A(r,n) = C(r-1,n-1) Where did it come from?
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Why are two answers different using the two equivalent formulas in combinatorics ?
Here is your other post: Of course v or k doesn't make a difference. There is an actual difference between (2) above and the second formula in the OP: Do you see it? Plus, I don't see anything there about the equivalence you're talking about here.
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Why are two answers different using the two equivalent formulas in combinatorics ?
I just did. The equation (2) there is very similar although not identical to your formula 2 here. And, nothing there says that the two formulas in the OP are equivalent, does it?
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To All Women in Science
My favorite woman in science is Rosalia Arshakovna, my math teacher in school, many eons ago. I don't even know her last name
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Why are two answers different using the two equivalent formulas in combinatorics ?
I don't know about this, but they are different for r=n=2. What is the source of the statement above?
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Why are two answers different using the two equivalent formulas in combinatorics ?
They are not equivalent.
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How many natural DNA/RNA bases are now known?
Yes, you did say splicing. It is my fault that I've missed it. I'm sorry. In my misunderstanding, I thought that X,Y,Z in your strings stand for arbitrary nucleotide bases. Now, after you've mentioned "hypothetical protein", I think they stand for arbitrary amino acids. Is this correct? Are we talking about mRNA splicing that occur after transcription and before translation? When introns get excised and exons get connected? I don't know about any redundancy associated with this splicing. I do know that alternative splicing is used to make different polypeptides from the same DNA sequence. This is somewhat opposite to redundancy.
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How many natural DNA/RNA bases are now known?
They are not the same. There is no cyclic symmetry. Your example looks like a frameshift mutation, which would lead to a very different peptide chain. Frameshift mutation - Wikipedia
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War Games: Russia Takes Ukraine, China Takes Taiwan. US Response?
Looks good!
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How many natural DNA/RNA bases are now known?
In fact, there is a lot of redundancy, i.e. the same amino acid being coded by several mRNA codons. There are 64 codons coding for only 20 amino acids: There seems to be quite a few modified bases occurring naturally, defined chemically. Here is a recent review: Natural, modified DNA bases - ScienceDirect
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Plant/Animal?
I don't see how fermentation could be "the oldest", because it uses organic compounds, which had to be produced from an inorganic matter first. Chemolithotrophs could've done that, for example.
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The "rational" foundations of religion?
Generally, yes. I don't think it is so for all people, all blanks.
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War Games: Russia Takes Ukraine, China Takes Taiwan. US Response?
Yes, maybe. Anyway, I hope that if they err, then only by undercounting.
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Examples of Awesome, Unexpected Beauty in Nature
I suspect that the corals were spawning and the fish were feasting on the eggs which were slowly floating upward.
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War Games: Russia Takes Ukraine, China Takes Taiwan. US Response?
Sometimes it seems to be a self-inflicted impairment. Just yesterday I had a phone call from a Russian acquaintance living long time in the US. Evidently, she didn't see the program that gave the nuclear bomb reasoning for shelling Kharkov, and started telling me about the Ukrainian ultra-nationalists shelling their own people to create the anti-Russian public opinion. On my questions, she said that Russian TV is the only truthful source of information about what is going on there, and all the rest is just fake news. (I've told her to never call me again and hang up.)
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War Games: Russia Takes Ukraine, China Takes Taiwan. US Response?
Right, no more doubts and confusion, everything is crystal clear now. Жить стало лучше, жить стало веселей.
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The "rational" foundations of religion?
It's not only us, humans. E.g. my dog barks when he sees something strange esp. if it's moving, until he figures out that it's not animate. Or, if animate, not a threat.
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War Games: Russia Takes Ukraine, China Takes Taiwan. US Response?
2 boats is perhaps correct - this is easy to count. The other numbers are more unreliable. Regardless, the reality is not what Putin expected. Or, anyone else.
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War Games: Russia Takes Ukraine, China Takes Taiwan. US Response?
Thank you.
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Biggest Bacterium Ever Discovered
The apology accepted. I did not mean to ask what I did not ask.
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Examples of Awesome, Unexpected Beauty in Nature
This underwater garden is created by fire corals. Beautiful to look at, but quite painful to touch. Actually, these colonies are not true corals, but other cnidarians. Here is another: