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OFFICIAL 13TH ROOT WORLD RANKING LIST




Contact:

info@13throot.com

MASTER CHALLENGE:

13TH ROOT OF A 200-DIGIT NUMBER



World records





Time(seconds)#13th rootDatePlaceRecordholderNationalityWitness statements 1Witness statements 2
513.55 s 7422391481494636373 April 6th, 2005 Paris, France Alexis Lemaire France?Maitre Albou
267.77 s 5772396280083911011 June 3rd, 2005 Paris, France Alexis Lemaire France Laurent DemonetMaitre Albou



History


On April 6th, 2005, Alexis Lemaire from France became the first human to calculate mentally the 13th root of a 200-digit number. He took 742 attempts and 513.55 seconds, exactly 500 seconds more than his first world record in 13.55 seconds with 100 digits.

83689566882369569398373286622256452247267804664938
36677497357558157303507570408962528802385783156837
68029349382010563433638555959315144504151494907094
19097704449305660268402771869624155688082648640933

His correct answer was 2391481494636373



On the 3rd of June in the same year, he needed only 267.77 seconds for the task #577in the official conditions
and took only 113 seconds for the task #40 before the official starting, in the same conditions(in front of TF1 TV)




The constant progress realised in the extraction of high order integer roots enables people to calculate the 13th roots from a 100-digit number very fast. But to double the number of unknown digits multiplies the difficulty by 10. Beginners can calculate a 13th root from a 100-digit number, but the 13th root from a 200-digit number needs several months of training.

Why the 13th root of a 200-digit number is the supreme category


  1. The record time for extracting the 13th root of a 100-digit number is 3.625 s by Alexis Lemaire for giving ALL the 8-digit number, and supposed 0.15 s by Jaime Garcia Serrano for giving the beginning of the 8-digit number.
    The time 3.625 s includes :
    reading the question, calculating the 13th root, displaying the 13th root

    This means the 13th root of a 100-digit number is an immediate calculation (1 second), and the recordholder will be the one with the fastest time for writing, not with the fastest time for calculating.
  2. Every left part and right part of the 13th root of a 100-digit number can be memorized: there are only 3 and 4 digits to be memorized
    Therefore the 13th root of a 100-digit number can be only a record of memorization, where as the 13th root of a 200-digit number is a true task of mental calculation
  3. the calculation of the 13th root of a 200-digit number cannot be done using calculators, whose accuracy doesn't reach 16 digits for a 13th root:
    The accuracy necessary for the 13th root of a 200-digit number is 16 digits.
  4. the 13th root of a 200-digit number begins always by 2, where as the 13th root of a 100-digit number begins always by 4
    Somebody who can calculate the 13th root of a 200-digit number will be able to calculate the non-integer 13th root of a 5-digit number, more common than a non-integer 13th root of a 9-digit number.
  5. The number of possibilities for the 13th root of a 200-digit number is 3 93 5 44 3961 77 5 93 with symetry/antisymetry, and whose 13th root is 13.26452, there are amazing coincidences which appear directly in the Book of the Revelation.

    Here are some quotes:


    Oleg Stepanov:
    "16 digits for me absolutely unbelievable. If you calculate Mentally it on 1 hour, on my opinion you goes to history like best calculator or best mathematician. Probably I can not do it on paper on this time. Also abacus not help me. And 8 digits calculator not help... "
    "This is new World for me. I even have no ideas how get 16 digits on answer...."
    "We interest because if it is really - this is big mathematic invent. For example, do you interesting man what can fly or somebody who can read mind?"

    Gert Mittring
    "The 13th. root from a 200-digit number is to difficult for me. In the best case, I have seven missing digits (from sixteen digits)!"

    Robert Fountain
    "To extract the 13th root from a 200 digit number within several minutes is a remarkable feat. If Alexis Lemaire can achieve this in the presence of suitably qualified witnesses, then he must be regarded as the greatest 'integer root calculator' in history."

    The calculation of the 13th root of a 200-digit number with a record time is the most difficult task of mental calculation which has ever appeared on the Earth.
    One of the main matters is to find the fastest method ...
    Others are to get the best use ...mentally.

    The 13th roots from a 200-digit number belong to the interval:

    2 030 917 620 904 736
    -
    2 424 462 017 082 328

    The exact number of possibilities is:
    3 935 44 3961 77 593, nearly 13.26452 raised to the 13th power




    The 13th power of

    2030917620904736

    is:


    10000000000000017859
    42640888119952040108
    90076134706402487522
    94463428245603911052
    49101519134847447306
    90251238365385129484
    73692444405926326323
    26025210657674458586
    67903028813661618695
    63181960799092473856



    The 13th power of

    2424462017082328

    is:



    99999999999999743031
    95204109698707368586
    70143875257942160271
    98214444230686699443
    81814942574664536133
    49154081532294524100
    82721678437084921498
    44644390984368284865
    21110390383678361448
    30722360637598466048



    The rules




    1. The record is both the fastest and most accurate calculation of the 13th root of a 200-digit number.
      The accuracy is measured by the number of attempts in a group of attempts, for a given event.
      The number of attempts (written #n)for that event is the number of proposed 200-digit numbers needed to break the record. Refusing one 200-digit number is included in the meaning of one attempt.
    2. The record is a test of straightforward mental calculation. The calculator should perform the calculation in his/her head without the aid of any other person and without using a calculating machines, computers, etc. nor may the calculator write the 13th root, the 16-digit number result, down.
    3. The competitor may choose to write the number from right to left, to left to right, or in any other order.
    4. The correction of a digit is not allowed, writing any other digit than a digit of the 16-digit 13th root is forbidden, and doubting digits(badly written) must not lead to a successful attempt.
    5. The number whose 13th root is to be calculated should be randomly selected by computer immediately prior to the calculation and should be displayed to the calculator on a computer screen, board, screen or similar. The given number must be the 13th power of a integer number which belongs to the range 2 030 917 620 904 736--2 424 462 017 082 328.
    6. The calculator should write down the answer.
    7. The timing begins when the number becomes visible to the competitor and ends at the end of writing the answer.
    8. The number of days of attempts is limited to 3 days per year
    9. However, if there is only one day of attempts in one year, 3 groups of attempts can be done for that day: the 3 days of attempts can be confounded. In this case, there will be 3 events. If there are only 2 days of attempts, one of these days may contain 2 groups of attempts:2 days of attempts may be confounded for that day, so that 3 groups of attempts(and no more) are allowed in one year
    10. The attempt should be announced very soon (some months in advance)to 13th_root@yahoogroups.com
    11. The exact date (day, hour) and location(adress) of the attempt must be definively announced at least 168 hours before the beginning of the attempt, as well as the name of the two official witnesses
    12. After this announcement, any change will unvalidate the day/group of attempts.
    13. Any group of attempts unvalidated is counted as a successless group of attempts.
    14. The record must break the existing world record both in accuracy and in speed
    15. The first record, by default, is 10100 seconds and 10100 attempts.
    16. The number of attempts must not be more than the number of attempts of the current record, and will likely be lower.
    17. Only the first record of the group of attempts will be accepted: this is the one whose number of previous attempts for that group is the lowest
    18. The name of the person making the attempt should be given, along with the date and place.
    19. There must be two independant witnesses(one should need no help and no advice from the other one)
    20. At least one of the official witnesses must be graduated in mathematics, physics or computer sciences(from recognized universities, not fake titles)
    21. At least one of the official witnesses must be an usher (official witness in law) or get this statut.
    22. The both witnesses must have read and understand the rules at least 168 hours before the attempts, and sent their approval to 13th_root@yahoogroups.com before this deadline.
    23. In this approval, they must say, without any lie, they are competent enough for all details of the attempt.
    24. Any false sentence written among the witnesses ' evidences will unvalidate the group of attempts, including any mistake.
    25. The press coverage doesn't count at all neither in the value of the record, neither as a witness.
    26. To prevent cheating, the competitor must accept any unknown checking and constraints set by the official witnesses; these ones must accept the unknown, secret checking and constraints set by info@13throot.com
    27. The competitor must also announce in advance the best performance he could get for the group of attempts: the better will be the performance, the higher will be the checking. If the performance is clearly much more amazing than announced, it will be not validated.
    28. All the 13th roots from a 200-digit number correctly calculated must be included in the documentation, in an official group of attempts
    29. the source code must be kept by the usher(and otherwitnesses) and the program must be compiled by the usher/witnesses, with written details of the process, immediately before the attempt. This rule allows to be sure that the source code of the program used for the record is known.
    30. The 2 witnesses MUST keep the sources codes and all the documentation
    31. Since many random numbers generators depends on the clock, the clock of the computer must be modified by the witnesses, within a 10 years range after the date of the event. For instance if the record is attempted on the 7/7/7, then the clock of the computer must be modified to belong to the range 8/7/7 - 7/7/17. No favorite date must be preferred in this clock's range.


    OFFICIAL 13TH ROOT WORLD RANKING LIST