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General Knowledge Quiz

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xotGD

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Barristers having to take the next case when it is their turn - next cab off the rank.
 

DaleCooper

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InkyScrolls

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A number which can be formed in two ways through the addition of cubes? 1729 is the lowest example of this (I forget the specific cubes used).
 

MotCO

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A number which can be formed in two ways through the addition of cubes? 1729 is the lowest example of this (I forget the specific cubes used).

I was looking at cubes and found that 1728 was a cube (12 x 12 x 12). So presumably adding 1 cubed would give you 1729.
 

DaleCooper

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Square numbers?
No
A number divisible by six other numbers?
No
I googled it and still don’t understand it o_O
I posed the question and I'm not sure I understand either.
I was looking at cubes and found that 1728 was a cube (12 x 12 x 12). So presumably adding 1 cubed would give you 1729.
So close.
A number which can be formed in two ways through the addition of cubes? 1729 is the lowest example of this (I forget the specific cubes used).
1^3 + 12^3 = 9^3 + 10^3 = 1729

Some can be formed in more than two ways but essentially you are correct, your turn...
 

MotCO

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No

No

I posed the question and I'm not sure I understand either.

So close.

1^3 + 12^3 = 9^3 + 10^3 = 1729

Some can be formed in more than two ways but essentially you are correct, your turn...
But why call it a taxicab number ???!!!
 

DaleCooper

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But why call it a taxicab number ???!!!

The name is derived from a conversation in about 1919 involving mathematicians G. H. Hardy and Srinivasa Ramanujan. As told by Hardy:

I remember once going to see him [Ramanujan] when he was lying ill at Putney. I had ridden in taxi-cab No. 1729, and remarked that the number seemed to be rather a dull one, and that I hoped it was not an unfavourable omen. "No," he replied, "it is a very interesting number; it is the smallest number expressible as the sum of two [positive] cubes in two different ways."
 

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