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rocdocmac last won the day on May 9 2021

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  1. Sent this via email on 30 April
  2. Nothing wrong with the "formula" in red! The distance here is expressed in parsec (pc), where 1 pc ~31 trillion km.
  3. For interest's sake, if no true fractions were involved at all, there is an alternative solution ...
  4. YAY! second number: the last digit of powers of 3 runs through the cycle (3971), with exponent divisible by 4 ending in 1. 556677 is 1mod4 so it ends in 3.
  5. Earlier today (whilst attending his birthday party) I asked Andy his age, but he said that I can figure that out easily by myself! All I had to do was to add four numbers together. The first of these four numbers is the last digit in the figure obtained when 2 is raised to the power of 667788 (2667788). Similarly, I had to find the last digit in the evaluation of 3556677, 7445566, and 8334455 to complete the sum. If today is the 12th of March 2020, when was Andy born?
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