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Dear fellow calcualtors, Recently I had a HD crash, so it can occur that someone does not get a reaction of mine on his message to me. I hope the experts can...
Dec 25, 2011
Dear fellow calculators, With my new harddisk and all the data of the former one lost, I wish you all a Merry Christmas and a prosperous New...
Dec 23, 2011
Dear fellow calculators, Please may I be a little bit proud on myself? I succeeeded in factoring the following numbers, which I got from George Lane. You...
Dec 11, 2011
The ability to perform the mental calculations and memorize things for competitions is enviable, but how (or do?) are these abilities used in everyday life? ...
Dec 9, 2011
Queries about the recent world records and Guinness book records
Hi to everyone I have some queries about the recent world records and Guinness book records in mental calculation in different areas I am providing them as...
Dec 5, 2011
My assessment of this year's Mental Calculations World Championship
Greetings to all. With apologies for the slowness of my actions, I have now completed writing my assessment of the Mental Calculations World Championship...
Dec 4, 2011
Question about number bases.....
Let's suppose one wants to convert a number written in base seven to base nine.. Example 2401 in base seven is 1181 in base nine. Both equal 883 in base...
Dec 4, 2011
Hello Every one, Thanks to all of you. One more request, Please guide me the best technic to calculate the 13th root of a 100 & 200 digit number . Thanking...
Dec 2, 2011
New World Record for Calendar Calculation
We have a new verified record for calculating the days of the week for all dates from one year (given in a random order, of course ;-) ): On 24 September 2011,...
Nov 29, 2011
Fw: [Mental Calculation] Re: Queries about the recent world records
... Van: A.W.A.P. Bouman Aan: MentalCalculation@
com Verzonden: dinsdag 29 november 2011 12:36 Onderwerp: Re: [Mental Calculation] Re: Queries about...
Nov 29, 2011
Happy Birthday to Priyanshi Somani
Priyanshi is now 4748 days or thirteen years old. She will be 5000 days old next July 25th. Jerry Newport...
Nov 24, 2011
the eagerly wanted numbers
Dear fellow calculators, A friend of mine, universitary Math teacher mailed me the list with 4 digit numbers, being the product of 2 prime numbers. Suffering...
Nov 19, 2011
Hi folks, I have recently completed the construction & testing of a file which generates prime factorisation problems. The file produces forty problems (in...
Nov 17, 2011
Re: the eagerly wanted numbers, list of four digit "semi-primes&q
Thanks a lot for this list, it gives a good workout to gain number insight, so far I don`t miss the 2s ;-). Reto [Non-text portions of this message have been...
Nov 17, 2011
Mental Calculations Groups In Philadelphia?
Hi, where in Philadelphia, Pa., can I go to join an in the flesh Mental Calculation group? Need some input on where practice sessions are held in Philly, if at...
Nov 16, 2011
New file uploaded to MentalCalculation
Hello, This email message is a notification to let you know that a file has been uploaded to the Files area of the MentalCalculation group. File :...
Nov 13, 2011
Wanted a list of semi- primes
Hello group members To get me some serious factor work on beginners level, I would love to have a list of semi-primes, unfortunately, the only one I stumbled...
Nov 12, 2011
Dear fellow calculators, If I remeber well Jerry made a suggestion for a kind of Excel file. I thought about it. This should sart with 3×3331, 5×1999,...
Nov 11, 2011
MC World Championship 2012
Hi folks. I've not seen any actviity here in the past few days, so I hope my membership link has not been broken for whatever reason. Anyway: I am now on...
Nov 7, 2011
Query: Possible world record for factoring six digit numbers....
My proposal is to have a record for factoring ten six digit numbers. Does anyone have a program that can generate such sets? There also is no record for...
Nov 2, 2011
fun way to practice factoring...
Whenever I see a four or five digit number and have the time, I try to factor that number and the next nineteen numbers. I call such a sequence a "run." Of...
Oct 26, 2011
Fw: GN 11-10-24
Dear fellow calculators, Hereunder you'll find my answer to Jerry Newport, as a reaction on the remarks of George Lane. Of course there is more to be said. If...
Oct 25, 2011
Dear fellow Calculators, I just received from Ralf Laue Leipzig the message that my new worldrecord has been recognised. It concerns 10 integer divisions of 10...
Oct 24, 2011
Welcome "jcvinet" to the Mental Calculation mailing list... and congratulations! You are the 2^10th member of the group! Ralf...
Oct 22, 2011
New article on extracting 13th roots of 100-digit numbers
Hi All, I posted a two-part essay on extracting 13th roots of 100-digit numbers on my blog yesterday that some of you may find interesting. It starts at ...
Oct 8, 2011
What we are planning is something like the first PI-OLYMPICS: Competitive and international. If you can forward a competitive pi-performance, we should be glad...
Oct 5, 2011
39;s Adventures in Numberland" now in German
Hello, One more German book, but this time it is a translation of a title already existing in English: Alex Bellos' book "Alex
39;s Adventures in Numberland"...
Oct 2, 2011
Very true Reto. Numbers become the ultimate international language....
Sep 29, 2011
good afternoon fellow calculators, Gert invited me as a guest of honour for the introduction of his new book, September 9, and was so kind to give me one of...
Sep 29, 2011
Gert in German TV Tomorrow
Gert Mittring will be a guest at "Stern TV" (German TV, channel RTL, 28 Sept 22:15). Among other things, he will extract a 98789th root from a 1.000.000 digit...
Sep 28, 2011
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