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GIMPS has discovered a new largest known prime number: 2^{82589933}1 (24,862,048 digits) Single Curio View: (Seek other curios for this number) A fourdigit number abcd is divisible by 13 if 13 divides a + 4b + 3c + 12d. d is calculated using the coefficients of a + 4b + 3c which shows if a threedigit number is divisible by 13. b * c / a = 12 and a fivedigit number is divisible by 13 if 13 divides a + 4b + 3c + 12d + 9e because the coefficients of c * d / b = 9. multiplying the last two coefficients and dividing by the one before them will always give the next term in this equation and therefore any number of any length can be checked for divisibility by 13. [Homewood]
Submitted: 20190115 13:51:18; Last Modified: 20190115 15:00:07.
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