Thursday, January 29, 2015

'The Pursuit of Beauty: Bounded Gaps Between Primes'

"No formula predicts the occurrence of primes—they behave as if they appear randomly. Euclid proved, in 300 B.C., that there is an infinite number of primes. If you imagine a line of all the numbers there are, with ordinary numbers in green and prime numbers in red, there are many red numbers at the beginning of the line: 2, 3, 5, 7, 11, 13, 17, 19, 23, 29, 31, 37, 41, 43, and 47 are the primes below fifty. There are twenty-five primes between one and a hundred; 168 between one and a thousand; and 78,498 between one and a million. As the primes get larger, they grow scarcer and the distances between them, the gaps, grow wider."

"Prime numbers have so many novel qualities, and are so enigmatic, that mathematicians have grown fetishistic about them. Twin primes are two apart. Cousin primes are four apart, sexy primes are six apart, and neighbor primes are adjacent at some greater remove. From “Prime Curios!,” by Chris Caldwell and G. L. Honaker, Jr., I know that an absolute prime is prime regardless of how its digits are arranged: 199; 919; 991. A beastly prime has 666 in the center. The number 700666007 is a beastly palindromic prime, since it reads the same forward and backward. A circular prime is prime through all its cycles or formulations: 1193, 1931, 9311, 3119. There are Cuban primes, Cullen primes, and curved-digit primes, which have only curved numerals—0, 6, 8, and 9. A prime from which you can remove numbers and still have a prime is a deletable prime, such as 1987. An emirp is prime even when you reverse it: 389, 983. Gigantic primes have more than ten thousand digits, and holey primes have only digits with holes (0, 4, 6, 8, and 9). There are Mersenne primes; minimal primes; naughty primes, which are made mostly from zeros (naughts); ordinary primes; Pierpont primes; plateau primes, which have the same interior numbers and smaller numbers on the ends, such as 1777771; snowball primes, which are prime even if you haven’t finished writing all the digits, like 73939133; Titanic primes; Wagstaff primes; Wall-Sun-Sun primes; Wolstenholme primes; Woodall primes; and Yarborough primes, which have neither a 0 nor a 1."

11 comments:

bagoh20 said...

Sounds like math nerds are horny little shits.

chickelit said...

Superficially, this reminds me of "magic numbers" in nuclear physics: link. If you imagine the Periodic Table as a number line with the number 1 being hydrogen and carbon being 6 etc. and so forth, then the elements 2 (He), 8 (O), 20 (Ca), 28 (Ni), 50 (Sn), 82 (Pb), and 126 (unbihexium, not yet made) are "prime" elements.

Unknown said...

Numbers are sexy. And mysterious.
Ponder the symbols, their forms, their symmetry and the way they communicate.

Rabel said...

Bounded gaps between primes.

This post creates visions of Kate Upton in my head. That's always a good thing. Well, almost always.

ricpic said...

I'm wondering whether the numbers 101 and 228 are primes? Those are the dimensions, 101 feet wide by 228 feet long, of the Parthenon.

I'm about halfway through one of the most exciting books I've ever read: The Parthenon Enigma. Author: Joan Breton Connelly. Can't recommend it highly enough. The subtitle is: A new understanding of the West's most iconic building and the people who made it. The book really delivers.

Lem the artificially intelligent said...

An unassuming teacher... not a tenured professor walking around with a brilliant brain. He is probably not the only one.

john said...

228 is not a prime number.

I doubt the Greeks used feet as their unit of measurement anyway. Probably cubits. That's what Noah used anyway, according to Bill Cosby. That's about 18 inches, which would make the length of the Parthenon 152 cubits, which is still not prime.

However, if a very tall person lived in Greek times, a cubit to him might be 21 inches, which would make his Parthenon 130 cubits, still not prime.

Maybe it would work in furlongs.

Eric the Fruit Bat said...

Tonight's dinner beer pairing was Allagash White and Stoudt's Helles.

Pretty damn tasty.

It could all be expressed in numbers, probably.

ricpic said...

OMG, john, I have to admit I didn't even stop to think that 5th century BC Greeks didn't measure in feet. Really red faced here.

Eric the Fruit Bat said...

Tomorrow my wife is making some kind of chipotle-adobo pot roast.

I intend to serve us both Sierra Nevada's Imperial Pilsner.

Just right.

XRay said...

Good post, Lem. Math is mostly a mystery to me.