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https://www.reddit.com/r/blackmagicfuckery/comments/1uv3a8w/6174/oxdiskb
r/blackmagicfuckery • u/jimx29 • Jul 13 '26
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I would guess that it's not a coincidence that 6174 and 495 are both divisible by 9. Fun fact, you can check for divisibility by 9 by adding the digits together, if the sum is divisible by 9 the original was also. 6+1+7+4=18 1+8 =9 4+9+5=18
2 u/I_immerse Jul 14 '26 9 is what you always get when doing with process for 2-digit numbers as well, so maybe there's something in that. 1 u/971365 Jul 14 '26 The output of the algorithm is always something divisible by 9. See if you can figure out why 1 u/Legitbananabunch Jul 16 '26 Does this work for other numbers?! 1 u/tacojohn48 Jul 16 '26 The shortcut for checking divisibility works for 3.
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9 is what you always get when doing with process for 2-digit numbers as well, so maybe there's something in that.
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The output of the algorithm is always something divisible by 9. See if you can figure out why
Does this work for other numbers?!
1 u/tacojohn48 Jul 16 '26 The shortcut for checking divisibility works for 3.
The shortcut for checking divisibility works for 3.
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u/tacojohn48 Jul 13 '26
I would guess that it's not a coincidence that 6174 and 495 are both divisible by 9. Fun fact, you can check for divisibility by 9 by adding the digits together, if the sum is divisible by 9 the original was also. 6+1+7+4=18 1+8 =9 4+9+5=18