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A374830
Decimal expansion of 17*(5 - 3*A136141)/100.
2
4, 5, 5, 6, 9, 0, 0, 9, 8, 7, 8, 4, 6, 0, 4, 4, 8, 4, 7, 8, 9, 1, 7, 2, 5, 9, 5, 4, 7, 3, 4, 6, 9, 3, 7, 8, 2, 3, 4, 4, 4, 1, 9, 1, 8, 5, 9, 7, 5, 7, 5, 1, 1, 5, 3, 6, 1, 3, 8, 6, 9, 0, 5, 6, 4, 8, 0, 7, 8, 3, 9, 5, 4, 7, 0, 4, 9, 0, 9, 6, 7, 1, 0, 4, 7, 6, 2, 6, 3, 3, 0, 0, 0, 1, 0, 6, 3, 8, 2, 6
OFFSET
0,1
COMMENTS
Lower bound of Product_{p prime} (1 - (1/(p*(p - 1)))*p^2/(p^2 + 1)) = A374831.
LINKS
Rafael Jakimczuk, Numbers of the form p-1 where p is prime, July 2024. See pp. 23-24.
FORMULA
Equals (3/5)*(17/20)*(1 - (A136141 - (1/2 + 1/6))) (see Jakimczuk).
Equals (125/153)*A374829.
EXAMPLE
0.45569009878460448478917259547346937823444191859757511536...
PROG
(PARI) 17*(5 - 3*sumeulerrat(1/(p*(p-1))))/100 \\ Amiram Eldar, Aug 20 2024
CROSSREFS
KEYWORD
nonn,cons
AUTHOR
Stefano Spezia, Jul 21 2024
STATUS
approved