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MCIII Number Theory 2.30 and 2.32

 
 
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Re: MCIII Number Theory 2.30 and 2.32
by Tina Jin - Sunday, 14 January 2024, 10:18 AM
 

Oh! a+b+c+d+e+f+g+h+i is 3*magic sum=3*1999=0 mod (3), but I proved earlier that a+b+c+d+e+f+g+h+i=1 (mod 3), so contradiction and 1999 cannot be the magic sum. (In fact, only integers, positive and negative, that are congruent to 0 mod 3 can be the magic sum)

Thanks!

Tina Jin