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1h
comment Polynomial factorisation - absolute value of coefficients
Ah, that explains it. Oops.
2h
comment Polynomial factorisation - absolute value of coefficients
You could also have $x^4+x^3-x^2-1 = (x-1)(x^3+2x^2+x+1)$. If I'm understanding arxiv.org/abs/0904.3057 correctly it claims that this is the unique quartic with height 1 and an irreducible factor of height greater than 1, in which case your example is a correction.
2h
answered Maximum absolute value of polynomial coefficients
2h
comment Finding $f'(1/3)$ when $f(x)= |x-(2/3)| $ by using the definition of derivative.
What problems do you have with absolute value? For $|\epsilon| < 1/3$ you should be able to ignore it.
2h
reviewed Close Finding $f'(1/3)$ when $f(x)= |x-(2/3)| $ by using the definition of derivative.
8h
comment Does $A193201$ count the partitions of $n$ of arbitrary dimension?
I'm not quite sure what I'm supposed to be looking at in the example you give of partitions of 4. For fixed layout, the preformatted text (the button that looks like {} in the editor, or the result of prepending 4 spaces to each line) is a bit easier than MathJAX.
1d
comment Math puzzle: 10 digit strings generations
Independent set problem
1d
comment Math puzzle: 10 digit strings generations
Not quite practical as a computational solution, but this can be reduced to the independent set problem on a graph of $10!$ nodes and $\frac{10! 7!}{2}$ edges.
Oct
21
revised Translate the following sentence into conjunctive normal form
edited tags
Oct
21
awarded  Revival
Oct
20
answered Question on data compression
Oct
15
answered Number of unlabeled simple graphs with $n$ nodes even for all $ n\ge 5$?
Oct
15
comment Number of unlabeled simple graphs with $n$ nodes even for all $ n\ge 5$?
Ah, it doesn't have simple in the title so my search didn't find it. Thanks for adding the link.
Oct
15
comment Number of unlabeled simple graphs with $n$ nodes even for all $ n\ge 5$?
Are you referring to A005470 (in which case you seem to be missing the very important word planar from the question) or to a different sequence?
Oct
12
reviewed Approve suggested edit on Limit of a sum is the sum of the limits: proof by induction
Oct
12
reviewed Close Can anyone help me prove block diagonal matrix?
Oct
12
reviewed Close Simple Question on Quantifier Logic
Oct
12
reviewed Close Growth of $\sum_{x=1}^{n-1} \left\lceil n-\sqrt{n^{2}-x^{2} } \right\rceil$
Oct
12
revised Counting all possible board positions in Quoridor
added 1987 characters in body
Oct
12
comment Counting all possible board positions in Quoridor
@lameK, I got 55 by writing a short computer program, but as I used an obscure language to do it I didn't see any benefit to sharing it. I'll add some examples to the last paragraph.