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Mathematics
RobPratt's user avatar
RobPratt's user avatar
RobPratt's user avatar
RobPratt
  • Member for 5 years, 1 month
  • Last seen this week
  • NC, USA
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How many permutations of n elements exist, such that for each pair of permutations, they are still distinct after removing any element?
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Let A be a 2n-element set. Find the number of pairings of A.
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Conditional expectation - alternative expression
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The probability of king of spades in a two card draw
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General conditions for a function to a probability generating function
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Uniform Convergence of Matrix Series
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Elementary proof that a binomial distribution with $p\ne \frac12$ is almost symmetric?
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Characterizing the Result of Lift and Project Method for Integer Programming
This is Theorem 3.12 in Optimization over Integers by Bertsimas and Weismantel.
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Characterizing the Result of Lift and Project Method for Integer Programming
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Is the polynomial $x^{105} - 9$ reducible over $\mathbb{Z}$?
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Generate Max Number of Sequences Separated by Hamming Distance of 3
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Legendre transformation is a continuous map
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How to find principal value of the cubic root?
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Cauchy-Schwarz application: $\left(\int_1^ef(x)dx \right)^2 \leq \int_1^e xf(x)^2dx$
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'deducing' a bound using the first order taylor series. How to make it more precise?
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Sign permanence of locally Lipschitz functions calculated on a sequence
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Find a fundamental unit by using the continued fraction
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Find the number of matrices over the finite field $\mathbb F_{19}$, whose minimal polynomial has a certain degree $m$.
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Minimum number of edges to be removed from a square grid so that no rectangles remain.
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Minimum number of edges to be removed from a square grid so that no rectangles remain.
OK, in graph theory that would be a $2 \times 2$ grid graph. Now for your $n=2$, that would have $9$ nodes and $12$ edges, and you are claiming that removing $2^2-2+1=3$ edges can eliminate all rectangles. What is a rectangle, and which $3$ edges do you remove?
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