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%I #10 Aug 20 2024 01:53:17
%S 3,7,2,2,9,5,8,3,2,3,4,0,3,6,3,1,4,1,1,6,7,6,2,4,6,6,9,5,0,4,4,6,8,4,
%T 4,6,2,6,9,9,6,8,8,8,7,7,4,3,1,1,6,9,2,4,3,1,4,8,5,8,5,8,3,0,4,5,8,1,
%U 5,6,8,2,5,7,3,9,3,0,5,2,8,6,8,0,3,6,1,6,2,8,2,6,8,0,6,0,7,7,0,1
%N Decimal expansion of 5*(5 - 3*A136141)/36.
%C Lower bound of Artin's constant A005596.
%H Rafael Jakimczuk, <a href="https://www.researchgate.net/publication/382207808_Numbers_of_the_form_p-1_where_p_is_prime">Numbers of the form p-1 where p is prime</a>, July 2024. See pp. 16-17.
%F Equals (1/2)*(5/6)*(1 - (A136141 - (1/2 + 1/6))) (see Jakimczuk).
%F Equals (153/125)*A374830.
%e 0.3722958323403631411676246695044684462699688877431169243...
%o (PARI) 5*(5 - 3*sumeulerrat(1/(p*(p-1))))/36 \\ _Amiram Eldar_, Aug 20 2024
%Y Cf. A005596, A136141, A374830.
%K nonn,cons
%O 0,1
%A _Stefano Spezia_, Jul 21 2024