• AccountMaker@slrpnk.net
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    1 year ago

    But what about 14, 21 and 28?

    14 - 4*2 = 6, not divisible by 7

    21 - 1*2 = 19, not divisible by 7

    28 - 8*2 = 12, not divisible by 7

    Or did I misunderstand the algorithm?

    EDIT: I didn’t realize that you remove the last digit when subtracting, got corrected in the replies.