User:PrimeFan

Update: I'm back from my vacation in France visiting historical military sites. The more sites I visited and the more people I talked to, the more I become convinced that France is a great ally of America and we ought to be very grateful for their help during WWII.

I am a fan of prime numbers. I have been researching "prime deserts", such as those enclosed by factorial primes. I also like to look for twin primes immediately preceding or following such deserts.

I have started articles on factorial prime, primorial prime, permutable prime, primorial, palindromic prime, negative one, one half, harmonic divisor number, strobogrammatic prime, Kaprekar number, Keith number, hexagonal number, pentagonal number, centered hexagonal number, heptagonal number, pyramidal number, tetrahedral number, cuban prime, octagonal number, unitary perfect number, Smith number, heteromecic number, star number, centered pentagonal number, centered square number, prime quadruplet, Motzkin number, centered triangular number, self number, untouchable number, nonagonal number (sometimes called "enneagonal number"), decagonal number, noncototient, Friedman number, Wedderburn-Etherington number, highly totient number, safe prime, Thabit number. I helped expand the stub on Harshad number. I have also edited pages on various numbers and mathematical concepts. It was, as a matter of fact, the articles on the individual integers from one to one hundred that at first drew me to Wikipedia.

Pages I Plan To Create (Or Work On If Created By Someone Else)

• Giuga number
• Rhombic dodecahedral number
• Unitary divisor (perhaps as an addition to the article on divisor)
• Unprimeable number? (Numbers such as 200, which in a given base can not be turned to a prime number with just one digit changed. I don't know if there's an official name for this concept bestowed by a professional mathematician).

Handy Links

• Sloane's OEIS Integer Sequence Look-Up (http://www.research.att.com/~njas/sequences/)
• Matthew Conroy's Java Dictionary of Numbers (http://www.madandmoonly.com/doctormatt/mathematics/numberDictionary/numbDict.htm)

Some Kinds Of Primes I've Been Thinking About

I'm fascinated by repunit primes in various bases while simultaneously feeling a bit guilty about devoting too much time to kinds of primes that are base-dependent, such as Smarandache-Wellin primes.

Related somewhat to base 10 repunits are primes of the form 10ⁿ + 1, which can be defined in a base-dependent way as well as in an algebraic form. So far the only primes I know of this form are 2 (which is a consequence of the algebraic definition, not the base-dependend one), 11 and 101. I've gone up to 10⁵⁰ + 1 and found no other primes, but at least I've noticed some patterns. If n is odd then 10ⁿ + 1 will be divisible by 11. If n is divisible by 2 but not by 4, then 10ⁿ + 1 will be divisible by 101. 73 and 137 are two other numbers I've seen a lot in the factorizations, but no pattern is apparent to me right now.

Also, I've been looking for primes greater than 41 such that n² + n + p equals a prime when n is between 0 and (p - 1). The primes less than 41 that meet this criterion are 3, 5, 7, 11 and 17. It should've been obvious to me that the number I'm looking for must be the lower of a twin prime, but at least knowing that helps me in my future searches. It's entirely possible that there are no such primes beyond 41, and that that can be proven by using congruences. But if it needs calculus to be proven, then I have an excuse for not knowing that proof.

With the enduring popularity of Mersenne primes and Fermat primes, I've wondered why people aren't researching other primes of the form pⁿ - (p - 1) or pⁿ + (p - 1). But they are. For example, I calculated the first six n for which 3ⁿ + 2 is prime, put that into Sloane's OEIS look-up, and sure enough, the second result was sequence A051783, "Numbers n such that 3^n + 2 is prime."

Lastly, I've been thinking about prime numbers that are also figurate numbers other than F₂, because every positive integer is, if nothing else, an F₂ figurate number. For example, 7 is a heptagonal number, 13 is a 13-gonal number and 127 is a 127-gonal number. What might not be so obvious is that 13 is a star number and 127 is a centered hexagonal number. As far as I can tell, centered polygonal numbers are the only kind of F_x<>2 number prime numbers can be.

McDononald's Monopoly Game Piece Numbers

I've noticed that McDonald's Monopoly game pieces have four digit numbers on them, and that the first two digits correspond to the iteration of the game and the second two to the location on the Monopoly board. (Thus, you can't win the million dollars with a Boardwalk from the first iteration of the game and a Park Place from the latest iteration of the game -- not that I have ever gotten a Boardwalk).

1. Mediterranean Avenue
2. Baltic Avenue
3. Oriental Avenue
4. Vermont Avenue
5. Connecticut Avenue
6. St. Charles Place
7. States Avenue
8. Virginia Avenue
9. St. James Place
10. Tennessee Avenue
11. New York Avenue
12. Kentucky Avenue
13. Indiana Avenue
14. Illinois Avenue
15. Atlantic Avenue
16. Ventnor Avenur
17. Marvin Gardens
18. Pacific Avenue
19. North Carolina Avenue
20. Pennsylvania Avenue
21. Park Place
22. Boardwalk
23. Reading Railroad
24. Pennsylvania Railroad
25. B. & O. Railroad
26. Short Line

Fanatic Deletionists Are The Scourge Of Wikipedia

Fanatic deletionists are worse than vandals. Vandals at least are obviously malevolent in their intentions. Fanatic deletionists talk like they have good intentions, and they might even believe it themselves. They wish to impose their views of what belongs in an encyclopedia solely on their own opinions, and spend more time marking items for deletion and arguing for deletion than creating new articles or improving existing articles.

Of course I'm a little biased, because fanatic deletionists want to delete the very articles that made me interested in Wikipedia in the first place. These articles on individual integers are something that Wikipedia can do that paper encyclopedias can't, and better achieve a goal of complete encyclopedicity.

My Life Story (If You Care To Hear It)

I served in the United States Navy for four years. After that, I worked in various factories for thirty-five years, getting cut short of retirement by a weird accident, from which I thankfully recovered quickly (relatively). During my time in the hospital, bored by television, I turned to books and gradually became interested in mathematical topics to an extent I would not have foreseen as a youngster. I stumbled on Wikipedia while researching prime numbers on the Web, and that brings us up to present times.

Awards and Such