47 (number)


47 is the natural number following 46 and preceding 48. It is a prime number, and appears in popular culture as the adopted favorite number of Pomona College and an obsession of the hip hop collective Pro Era.

In mathematics

Forty-seven is the fifteenth prime number, a safe prime, the thirteenth supersingular prime, and the sixth Lucas prime. Forty-seven is a highly cototient number. It is an Eisenstein prime with no imaginary part and real part of the form.
It is a Lucas number. It is also a Keith number because its digits appear as successive terms earlier in the series of Lucas numbers: 2, 1, 3, 4, 7, 11, 18, 29, 47,...
Forty-seven is a strictly non-palindromic number.
Its representation in binary being 00101111, 47 is a prime Thabit number, and as such is related to the pair of amicable numbers.
Forty-seven is a Carol number.

In science

Pomona College

Forty-seven has been the favorite number of Pomona College, California, United States, since 1964. A mathematical proof, written in 1964 by Professor Donald Bentley, supposedly demonstrates that all numbers are equal to 47. However, Bentley offered it as a "joke proof" to further a popular student research project that listed real and imaginative "47 sightings". Bentley used the invalid proof to introduce his students to the concept of mathematical proofs. The proof used limits to show that the sum of the two equal sides of an isosceles triangle is equal to the base side. Bentley chose forty-seven as the base side, but he could have used any number.

''Star Trek''

graduated from Pomona College in 1979 and went on to become one of the story writers of '. Menosky "infected" other Star Trek writers with an enthusiasm for the number 47. As a result, 47, its reverse 74, its multiples, or combinations of 47 occur in a large number of episodes of the program and its spin-offs ', ', and ', usually in the form of dialogue, on-screen labels, or computer screens. For example:
J. J. Abrams, who produced and directed Star Trek, frequently uses the number 47 in his productions, including episodes of his TV series Fringe. In the Season 1 episode "Bad Dreams", aired shortly before the release of Star Trek in theaters, Nick Lane's bulletin board features a large centrally-located sheet of paper with only the number 47 in huge typeface. It recurs in the series: for example, 47 minutes being the maximum amount of time for a time chamber in the series to last, and there being exactly 47 shapeshifters. J.J. Abrams continues to incorporate 47 into movies and series he produces and directs.
The final sequence of Mission Impossible: Ghost Protocol takes place on Pier 47.
There are many 47s in Fringe, Alias, and Revolution. In , the thermal oscillator is located in Precinct 47. In the Season 1 episode "Soul Train" of the series Revolution, the characters are involved with an old train engine where the engine number happens to be 47.

2012 U.S. presidential election

During the 2012 election, Republican candidate Mitt Romney made a comment claiming that 47 percent of Americans do not pay any income tax. Since the comment potentially sabotaged his chances of winning the election against Barack Obama, the term "47 percent" has been used by critics to describe actions that could potentially damage a political candidate. For example, during the 2016 election, Hillary Clinton's speech labeling half Donald Trump's supporters as "deplorable" was compared by critics to Romney's 47 percent speech.

Pro Era

The Brooklyn-based hip hop collective Pro Era and its late co-founder Jamal Dewar, better known by his stage name Capital Steez, have made references to the number 47 in various songs by members of the group. The design of one of Pro Era's logos is the number 47 with its digits joined together. The origins of the group's connection with the number can be linked to the production of Capital Steez's 2012 debut mixtape AmeriKKKan Korruption. The rapper was heavily fixated with the number during that time; he felt that 47 was a perfect expression of balance in the world, representing the tension between the heart and the brain.

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