cultural reviewer and dabbler in stylistic premonitions

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Joined 2 years ago
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Cake day: January 17th, 2022

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  • It’s literally a covert project funded by google to both sell pixels and harvest data of “privooocy” minded users. It seems to be working well.

    Is it actually funded by Google? Citation needed.

    I would assume Graphene users make up a statistically insignificant number of Pixel buyers, and most of the users of it I’ve met opt to use it without any Google services.


  • Arthur Besse@lemmy.mlto196@lemmy.blahaj.zonethere is no rule
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    1 month ago

    17 × 59 = 10003

    you’ve got an extra zero in there, and you forgot the 1, but the rest of your divisors match my crude brute-force approach:

    >>> n=31521281
    >>> d = [ x for x in range(1,n//2+1) if not n%x ]
    >>> d
    [1, 11, 17, 59, 187, 649, 1003, 2857, 11033, 31427, 48569, 168563, 534259, 1854193, 2865571]
    >>> yours=list(map(int,"11+17+59+2857+11033+534259+1854193+2865571+168563+48569+10003+31427+649+187".split("+")))
    >>> set(yours) - set(d)
    {10003}
    >>> set(d) - set(yours)
    {1, 1003}
    >>> sum(d)
    5518399
    

    same conclusion though: 5518399 also ≠ 31521281

    bonus nonsense
    >>> isperfect = lambda n: n == sum(x for x in range(1,n//2+1) if not n%x)
    >>> [n for n in range(1, 10000) if isperfect(n)]
    [6, 28, 496, 8128]
    

    (from https://oeis.org/A000396 i see the next perfect number after 8128 is 33550336 which is too big for me to wait for the naive approach above to test…)

    more bonus nonsense
    >>> divisors_if_perfect = lambda n: n == sum(d:=[x for x in range(1,n//2+1) if not n%x]) and d
    >>> print("\n".join(f"{n:>5} == sum{tuple(d)}" for n in range(10000) if (d:=divisors_if_perfect(n))))
        6 == sum(1, 2, 3)
       28 == sum(1, 2, 4, 7, 14)
      496 == sum(1, 2, 4, 8, 16, 31, 62, 124, 248)
     8128 == sum(1, 2, 4, 8, 16, 32, 64, 127, 254, 508, 1016, 2032, 4064)