Recent content by AntonVrba

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    Graduate N=a^2+b^2+c^2, a.b.c.N are all integers(>0)

    every positive integer is a sum of 4 squares http://www.alpertron.com.ar/4SQUARES.HTM and http://www.alpertron.com.ar/FSQUARES.HTM
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    Graduate Congruences of (x^n-2) and its factors

    Oops sorry - I forgot to add n is even
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    Graduate Congruences of (x^n-2) and its factors

    It is easy to show that for all odd x that: (x^n-2) = 7 (mod 8) but why are the factors of above either congruent 1 or 7 modula 8, i.e factor(x^n-2) = {1,7} (mod 8) can anyone give me a hint. regards Anton
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    Undergrad Prime counting function- no error.

    Congratulations - can you tell us the number it returns for the largest known prime 2^25964951-1 By the way above prime has 7816230 decicimal digitits
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    Graduate Congruent equality - how to prove?

    Love your joke :smile: - by your theory I should be rich - alas - far from it :frown: . Yes I know Fermats small theorem Mod(5^(13-3),13) = Mod(5^10,13) = 5 Mod(5^(26-4),13) = Mod(5^22,13) = 5 And Fermats Little theorom Mod(5^13,13) = 5 or Mod(5^12,13)=1 Ok now I see -...
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    Graduate Congruent equality - how to prove?

    If p is a prime or psuedo-prime base b then the following equality holds for all values \mbox{p , b} , but how to prove it? b^{2p-4}\equiv\mbox{x (mod p)}\Longleftrightarrow b^{p-3}\equiv\mbox{x (mod p)} we are talking about one and the same value for x in the above two congruencies...
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    Do Sliding Block Puzzles Offer Unique Challenges?

    You all thought it not possible, try following 84 moves :biggrin: A1236 63266 A4578 87588 A6623 A8857 A8821 46628 83126 64218 63A75 26814 2A318 642A6 6836A 2488A 66756 6753A 88428 8241A
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    Do Sliding Block Puzzles Offer Unique Challenges?

    Enjoy. http://www.puzzleworld.org/SlidingBlockPuzzles/quzzle.htm To start, try A1236 63266 A4578 ...
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    High School 0/0 Anything divided by zero is undefined

    and what about \frac{Sin(x)}{x} at x=0 above is defined as 1, hence 0/0=1 by logic deduction
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    Undergrad Understanding the Definition and Status of -1 as a Prime Number

    We all know the definition of prime numbers and the first prime number is always 2. Why is -1 not listed as a prime number? , it qualifies as it passes all tests for a prime number.
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    Pilot Solves Navigation Problem with Handwritten Sign

    Atrus you are correct - I would prefer the "Microsoft Building"
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    Pilot Solves Navigation Problem with Handwritten Sign

    A helicopter was flying around above Seattle when an electrical malfunction disabled all the navigation and communications equipment. The pilot saw a tall building, flew toward it, circled, drew a handwritten sign saying "Where am I?" and held it in the helicopter's window. People in the tall...
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    Graduate How Does the Squared Pattern Relate to Prime Numbers?

    you will find the solution only by using primes
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    High School What Number Completes the Math Pattern?

    looks like an extract from a telephone directory to me - but which one?
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    Graduate How Does the Squared Pattern Relate to Prime Numbers?

    Yes rows AND columns can be expanded indefinately. yes it is column not columb but then the b is next to the n on the keyboard