Counter Examples

Mathematics Dictionary
Dr. K. G. Shih


Keyword - Amicable Numbers

Index .......... Contents of Mathematics Dictionary by index
Sections ....... Contents of Mathematics Dictionary by chapters
Program ABI .... Application of Mathematics Dictionary on Web

Q1 : What is amicable number ?
Answer
    * The sum of factors of 1st number = 2nd number.
    * The sum of factors of 2nd number = 1st number.
    * Then these two numbers are called amicable pairs

    [Example] 220 and 284 are amicable pairs.
    [Example] 1 + 2 + 4 + 71 + 142 = 220
    [Example] Prove that sum of factors of 220 = 284

Q2 : Can we have more pairs ?
Answer : Pairs between 1000 and 10000 are
    1184 and 1210
    2620 and 2924
    5052 and 5564
    6232 and 6368
    Reference : p234-p235 Computer Math by Dr shih
    Reference : Mathematics Dictionary Chapter 1 program 9 and 24

Q3 : Where can we find more ? Reference
    * P234-235. Computer Mathematics by Dr. K. G. Shih
    * Mathematics Dictionary Program 01 09
    * Mathematics Dictionary Program 01 24

Q4 : What can we learn related with this keyword ? Answer
    * Euler (1707-1783) discovered 59 amicable number pairs
    * If sum of factors = number itself, it is a perfect number
    * 1st perfect number is 6
    * 2nd perfect number is 28
    * 3rd perfect number is 496
    [Example]
      1,2,3 are factors of 6 and 1+2+3=6
      Is is 1st perfect number
      Prove that 28 is the 2nd perfect number

      Prove that 496 is the 3rd perfect number
      What is the 4th perfect number ?
      See keyword Perfect number in Math Dictionary

Q5 : How to find Amicable number from Math Dictionary ? Answer
    * You should download MD2002 to run on your computer
    * You can find it in chapter 1 by Program ABD
    * You can find it by keyword Amicable in Program ABCE
    > * You can find it by keyword Amicable in Program ABE

    * MD2002 is simple in use : * E.g. Use Program ABC : Click Text A and Click Amicalbe
    * E.g. Use Program ABD : Chapter 1 and program 9
    * E.g. Use Program ABE : Find Amicable in index and click it

Q6 : Amicable sample from software MD2002

Mathematics Dictionay
Dr. K. G. shih

11 Lantana Terrace, Dartmouth, NS, Canada. B2X 3L3
phone .......... (902) 434 1981
email .......... kshih@hfx.eastlink.ca
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Webpage ........ Mathematics Dictionary

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