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Equation 2 · Part 1 · Cities Are Organisms That Refuse to Die: Urban Evolution to 2100

Symbol N

NN
NN

What this part means

N is a part of this expression. Its role is fixed by the surrounding article and by the operations shown in the formula.

Its job in the formula

N is a part of this expression. Its role is fixed by the surrounding article and by the operations shown in the formula.

The passage around this formula

…infrastructure scale sublinearly: length of electrical cable 0.87, road surface 0.83, gasoline stations 0.77, gasoline sales 0.79 [ 1 ] . In the compact notation the paper made famous, a quantity Y relates to population N as

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A variable is a named place for a value. Its letter is a local label: x can mean position in one formula and a data point in another.

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Sources cited in the surrounding passage

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