Number One is the Lonliest Number, a song by John Farnham.
In North America, the number 8 is considered lucky, or rather a popular favourite number. Its shape represents infinity. The number 7 is also lucky. It's made up of the numbers 3 and 4, which are the points of the triangle and the square, respectively - what the mathematician Pythagorous called (the only) pure forms. The number 13 is unlucky. It's origin, variation in moon cycles (months). Some years had an even 12, some had the odd 13. That extra number was odd, hence unlucky.
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