MHB Find p-adic valuation and p-norm

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The discussion focuses on calculating the p-adic valuation and p-norm for the fractions x = 3/686 and x = 56/12 with respect to primes p = 7 and p = 5. For x = 3/686, the calculations yield a p-adic valuation of w_7(3/686) = -3 and w_5(3/686) = 0, while the p-norms are |3/686|_7 = 343 and |3/686|_5 = 1. For x = 56/12, the results show w_7(56/12) = 1 and w_5(56/12) = 0, with p-norms |56/12|_7 = 1/7 and |56/12|_5 = 1. The responses confirm that the calculations presented are correct. Overall, the thread validates the user's findings on p-adic valuations and norms.
evinda
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Hi! (Nerd)

I have to find the values $w_p(x)$ and $|x|_p$ for $x=\frac{3}{686}$ and $x=\frac{56}{12}$ for $p=7,5$.

That's what I have tried:

  • $$x=\frac{3}{686}=\frac{3}{2 \cdot 7^3}=3 \cdot 2^{-1} \cdot 7^{-3} $$

    $$p=7: x=7^{-3} \cdot 3 \cdot 2^{-1} \mapsto 7^3=343= \left |\frac{3}{686} \right|_7$$

    $$w_7 \left ( \frac{3}{686}\right)=-3$$

    $$p=5: x=5^0 \cdot 7^{-3} \cdot 3 \cdot 2^{-1} \mapsto 5^{-0}=1=\left |\frac{3}{686} \right |_5$$

    $$w_5 \left ( \frac{3}{686}\right)=0$$
    $$$$
  • $$x=\frac{56}{12}=2 \cdot 7 \cdot 3^{-1} $$

    $$p=7: x=7^1 \cdot 2 \cdot 3^{-1} \mapsto 7^{-1}=\frac{1}{7}=\left |\frac{56}{12} \right |_7$$

    $$w_7 \left ( \frac{56}{12}\right)=1$$

    $$p=5: x=5^0 \cdot 2 \cdot 7 \cdot 3^{-1} \mapsto 5^{-0}=1=\left |\frac{56}{12} \right |_5$$

    $$w_5 \left ( \frac{56}{12}\right)=0$$

Could you tell me if it is right or if I have done something wrong? (Thinking)
 
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Looks good to me. (Yes)
 
mathbalarka said:
Looks good to me. (Yes)

Nice! Thanks a lot! (Smile)
 
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