Math Forum / Mathematics / Algebra Help / November 2008

How do I write, formally, the definition of a set of pairs (a,b) of members
of a set A, for which each a in (a,b) is a distinct member of A and each b
in (a,b) is a distinct member of A?
With thanks in a advance.

I've got this problem with the idea of adding to a set by the union
function. I want to incorporate one specific value, a, into a set A(n) whose
specific members are determined only by the vague reference 'for n in ....'.
By saying A \/{a} I don't know if it implies that the ...

Let x and y be integers such that 0<x<y.
Let G(x,y) be the number of multiples in an interval of length (y-x+1) that
contain no factor in [2,y].
If p is a prime in the set of primes in [1,y], is there a standard proof (or

I have got a lot of values n that are integers and when I am using
combinatorics I have to go through several levels of calculation. First I
take n for which g(n)=x and then I take a set of values, each of which will
be ascribed a distinct n, that are x-1-combinations of  ...

Two quick questions, if I may:
1) Is there a positive equivalent, that is a separate symbol from the plus
sign, to the set minus sign "\" ? \setplus is rejected by Latex.
Currently I've got, for my set L(n),

While working on finding g(x) where O(g(x)) is an upper bound for
                    i(x) = 1 + Fib(n-1) + Fib(n-2)
where Fib(n) is the Fibonacci function, I had to evaluate
                   lim F(n)/F(n+1) as n -> infinity.

 I am trying to write something to do with combinatorics, in which I know
very little.
 Take a set Delta that is {A,B, .... etc.} of cardinality c. I want to know
how to write out definitions of sets each of which constitutes the possible

verify that
[log with base(3/4)*log with base(8){(x^2 +7)}]+[log with
base(1/2)*log(1/4){x^2 +7}^-1] = -2