It is certainly hard to square these numbers with rising tax revenues and significant increases in employment.

BBC: UK GDP: A nasty surprise and a puzzle

Not surprisingly, gross revenue numbers per square foot on average are now often higher for restaurant operations than for retail operations.

FORBES: Fine Dining - At A Shopping Mall?

And what, too, to make of the square roots of negative numbers?

ECONOMIST: Arguments over what counts as a number

The vision was sustained by the individuals, foundations and planners within the official agencies to whom the city's great theatrical tradition was more important than running the numbers on commercial square footage.

WSJ: Miracle on 42nd Street

So the obvious way to find out whether a number is prime is to try dividing it by all numbers which are smaller than its square root.

ECONOMIST: Number theory

Casio has redesigned the ClassPad series' software keyboard to make this new model easier to use, organizing functions to correspond to three levels of learning difficulty, beginning with basic functions used by everyone like fractions, square roots, and trigonometric functions, then advanced functions like differential calculus, complex compound numbers, and sigma calculations, and finally even more advanced calculations including piecewise and user-defined formulas.

ENGADGET: Casio's touchscreen graphing calculator arrives in 2013, makes the TI-84+ look dated