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# Er. B-cup 36''?
(I helped save b3ta! The Alchemist king of the needlessly complicated, Wed 20 May 2009, 17:57, archived)
# Haha, too small and too many inches there.
I've not been B since I was about 11 or 12.
(I helped save b3ta! Rev. Cleo still alive, Wed 20 May 2009, 18:03, archived)
# Fair enough.
Now you have to guess this:

1) given a sequence Xr = (x0, x1, ... , xn) where xi is less than or equal to xi+1 for i in n
2) where each x in Xr is taken from the list of numbers between 1 and 2 to the power n
3) what is the size of X, the set of all such sequences?
(I helped save b3ta! The Alchemist king of the needlessly complicated, Wed 20 May 2009, 18:26, archived)
# That sentence doesn't end properly.
(I helped save b3ta! Rev. Cleo still alive, Wed 20 May 2009, 18:27, archived)
# Sorry,
it had an < sign
(I helped save b3ta! The Alchemist king of the needlessly complicated, Wed 20 May 2009, 18:29, archived)
# Thought so. Damn chevrons.
And I stopped complex mathematical stuff at A level maths.

So this just confuses me to where the i comes from. Isn't i the root of -2?
(I helped save b3ta! Rev. Cleo still alive, Wed 20 May 2009, 18:33, archived)
# i is just an index.
but the answer, for n = (3, 4, 5) is (84, 3060, 324632). I wish I had the maths to provide a general formula :(
(I helped save b3ta! The Alchemist king of the needlessly complicated, Wed 20 May 2009, 18:44, archived)
# I see.
Interesting.
(I helped save b3ta! Rev. Cleo still alive, Wed 20 May 2009, 18:47, archived)
# ha! :) I expect that was typed with a straight face like this, :|
even more interesting is that a subset of the sequences in X can produce another set of sequences B, where each bi in B is just the binary representation of xi with length n (left-padded with 0s).

Arranged into a square, these sequences in B form n by n matrices that are the adjacency matrix of a graph, and the set of graphs so produced are non-isomorphic.

Which is pretty cool, I think.
(I helped save b3ta! The Alchemist king of the needlessly complicated, Wed 20 May 2009, 18:56, archived)
# This both confuses and interests me.
Is it similar to the Mandelbrot set?
(I helped save b3ta! Rev. Cleo still alive, Wed 20 May 2009, 19:17, archived)
# :) no, not at all. or, I should say, "not as far as I know", which isn't very far, when it comes to maths.
(I helped save b3ta! The Alchemist king of the needlessly complicated, Wed 20 May 2009, 19:37, archived)