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You are not logged in. #1 20130614 00:49:09
Words for combinatorial mathsI'm having trouble fitting words into the following definitions. #2 20130614 00:51:46
Re: Words for combinatorial mathsHi; In mathematics, you don't understand things. You just get used to them. I have the result, but I do not yet know how to get it. All physicists, and a good many quite respectable mathematicians are contemptuous about proof. #3 20130614 01:24:38
Re: Words for combinatorial mathsGiven a set of n nonrecurring objects, , and a number k such that . Find words that fit in the following definition.a, A way of arranging all n objects (order matters, formula ). b, A way of choosing AND arranging k out of the n objects (order matters, formula ) c, A way of choosing k out of the n objects (order does NOT matters, formula ) d, A way of choosing AND arranging k objects from S, repetition allowed, order matters. e, A way of choosing k objects from S, repetition allowed, order does NOT matters. Note: If not mentioned, repetition is not allowed. P.S. Sorry for the older post, it's just an experiment. I forgot to put the formula tag in. Again, sorry. Last edited by phanthanhtom (20130614 01:26:15) #4 20130614 01:29:18
Re: Words for combinatorial mathsFor d) that is all you have? In mathematics, you don't understand things. You just get used to them. I have the result, but I do not yet know how to get it. All physicists, and a good many quite respectable mathematicians are contemptuous about proof. #5 20130614 01:30:17
Re: Words for combinatorial mathsWhat do you mean? I don't know the formula! Last edited by phanthanhtom (20130614 01:30:39) #6 20130614 01:36:13
Re: Words for combinatorial mathsHow many are being picked from S? n objects? 3 objects k  n objects? In mathematics, you don't understand things. You just get used to them. I have the result, but I do not yet know how to get it. All physicists, and a good many quite respectable mathematicians are contemptuous about proof. #7 20130614 01:39:05
Re: Words for combinatorial mathsd. For example if k=5, then (a1, a2, a2, a3, a3) would be a solution (repetition allowed), and it would be different from, say, (a1, a2, a3, a2, a3). #8 20130614 01:47:29
Re: Words for combinatorial mathsHi;
Choosing k objects from n distinct objects with repetition and order matters is n ^ k In mathematics, you don't understand things. You just get used to them. I have the result, but I do not yet know how to get it. All physicists, and a good many quite respectable mathematicians are contemptuous about proof. #9 20130614 01:49:32
Re: Words for combinatorial mathsFor k=3, n=5: Last edited by phanthanhtom (20130614 01:50:35) #11 20130614 21:59:08
Re: Words for combinatorial mathsHi; In mathematics, you don't understand things. You just get used to them. I have the result, but I do not yet know how to get it. All physicists, and a good many quite respectable mathematicians are contemptuous about proof. #12 20130614 23:06:31
Re: Words for combinatorial mathsThanks, but I stress again that I need the official NAME, not the formulae. #13 20130614 23:09:25
Re: Words for combinatorial mathsHi; In mathematics, you don't understand things. You just get used to them. I have the result, but I do not yet know how to get it. All physicists, and a good many quite respectable mathematicians are contemptuous about proof. #14 20130615 01:05:03
Re: Words for combinatorial mathsThank you. The Vietnamese names for them roughly translates to: #15 20130615 01:07:02
Re: Words for combinatorial mathsA partial permutation? Is that when you do not use all the elements of the set? In mathematics, you don't understand things. You just get used to them. I have the result, but I do not yet know how to get it. All physicists, and a good many quite respectable mathematicians are contemptuous about proof. #17 20130615 01:14:22
Re: Words for combinatorial mathsIn other words, partial permutation <=> k < n #18 20130615 01:15:14
Re: Words for combinatorial mathsThey are best done with exponential generating functions. In mathematics, you don't understand things. You just get used to them. I have the result, but I do not yet know how to get it. All physicists, and a good many quite respectable mathematicians are contemptuous about proof. #19 20130615 01:15:31
Re: Words for combinatorial mathsAgain, I am looking for alternative names. I finished reading that twelvefold Wikipedia article. Formulae enough. #20 20130615 01:17:09
Re: Words for combinatorial mathsOkay, if I see anything different I will add it here. In mathematics, you don't understand things. You just get used to them. I have the result, but I do not yet know how to get it. All physicists, and a good many quite respectable mathematicians are contemptuous about proof. 