h2g2 The Hitchhiker's Guide to the Galaxy: Earth Edition

News: Neil Diamond married (see Original Post).

Personal news: Really close to getting kicked off of library comps today, so .

2+3*5^7=234377=112*13*149 is a good new one (to me).

Hmmm. I did not preview that. It was supposed to be square. I guess I forgot something about this site as opposed to others, I have been here so little.

My new computer produced a new submission to Prime Curios! based on the number 8535888851411555386, a palindrome of 17 digits in bases 13 and 15. The next time I looked at Wikipedia (about 24 hours after), my attention was brought to the historic protests of 8/8/88 in Myanmar. This was right after I had submitted 100001111122223333444455556666777798889899 (42-digit, smallest prime with a composite number of copies of each digit).

Oh dear; actually I never liked counting.I am wrecked and beyond help.

Here is one that I really like, and there are actually quite a lot of nice things about palindromic primes that are close to having a palindromic index, PAL. But I don't really have a whole lot of those details organized yet.

http://primes.utm.edu/curios/page.php/112111211.html

Another pretty one (but not huge): The number of 9-digit emirps with leading digit 9 is 1007777 (which happens to be an emirpimes, btw).

Reminder: An emirp is a prime whose (base 10 unless stipulated otherwise) reversal is a prime other than itself, a semiprime is a product of two primes (I think it usually is defined to include squares of primes), and emirpimeses (yes, that is the plural) bear the same relationship to semiprimes that emirps do to primes.

Eveneye, I am sorry but what is it about these numbers that is supernatural? Personally I am practically ennumerate and have always considered maths to be an UNNATURAL science. But maths on the whole are a fairly human and arbitrary system of explanations and I would not think that they are supernatural in any way, but I'm openminded. I just wanted to know your rational for including it in this particular thread.

'Innumerate', 'Rationale'.

Well, the thread had long ago become little but a chat on my findings, or even a little monologue. The littler ones are not much but ordinary research results, coincidences of a non-convincing nature that I just want to add. Things like the recently linked (regarding 112111211) bear on my claim that I mediate. I'm really not itching to get into a longer explanation, and I hardly ever am online at all, much less at hootoo these days. Maybe in some months' time I will be more active. Good to have a visit from somebody news, in any case.

New*

Btw, I did actually lose my freedom to use the college library, then returned very briefly during what was supposed to be a two week period I should not return. The incident was not overuse, actually, though that started it. I lost my temper when trying to compose a short replacement email to a mathematician for a long one I lost when a computer shut down and the library security guard told me to leave right after the 15-minute closing warning. As I used some language essentially directed at the computer that I cannot repeat, this resulted in a ban. Apparently 20-year old college students have virgin ears I should not defile. Police called me on my cell, so I said if I ever again need a college library I will go to one in the city and stay clear of the one here.

Cor, interesting The only college library I'm allowed to use is 200 miles away and costs £300 to get there and back. It is cheaper to buy the book.

Oh, wow! Yes, is probably different in some countries. Or did you cause a problem? I am just assuming that college libraries cannot really be used at all by the general public there without at least paying an annual fee.

Anyway, another nice new one: The sums of the first 8 and first 14 quadruple iterates of the nth-prime function are 6226 and 44044, respectively.

College libraries are not public here. You cannot even pay to be a member unless your invited, by virtue of being a student, staff or alumni or some other arrangement. My old university has a library of at least 3 million titles but cost a lot. However I'm a member of a royal society that has an arrangement with various colleges and ancient societies. But they are a long way away.

Wow, that is surprising. I know of one major college library system here--the only one I have checked--that permits BORROWING PRIVILEGES for its whole system excluding the Law School library (which is wholly off limits) for a really reasonable cost. And at least for the main library building, reading in it only requires valid ID.

Here's another: The 9th complete reverse concatenation prime in binary--the 9th base-2 analogue of 82818079...321--begins with 110. Only surprising that there are so many, but in its 185 (around: I don't have it with me) digits in decimal there are four copies of the triple-digit string '444', and there are another 3 triple-digit strings jammed together in a 13-digit string.

Actually, it is 196 digits, with a total of 37 copies of the digit 4. With 22 copies of the digits 0 and of the digit 5 as the maximum for other digits, this means removing the four '444' sequences would still leave more copies of the digit 4 than any other.

Another little one:
There are 19 numbers not requiring symbols beyond the decimal digits in any base under 19, the two largest are 19 digits long in decimal, and the only multidigit prime among them is 19.