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%I #61 Oct 30 2022 15:06:20
%S 1,5,1,8,6,7,7,8,8,1,2,3,0,1
%N Decimal expansion of the sum of the alternating series of reciprocals of composite numbers.
%H Eric Weisstein's World of Mathematics, <a href="http://mathworld.wolfram.com/PrimeSums.html">Prime Sums</a>
%H Eric Weisstein's World of Mathematics, <a href="http://mathworld.wolfram.com/PrimeZetaFunction.html">Prime Zeta Function</a>
%H Wikipedia, <a href="http://en.wikipedia.org/wiki/Prime_zeta_function">Prime Zeta Function</a>
%F -Sum_{k>=1} (-1)^k/A002808(k) = 1/4 - 1/6 + 1/8 - 1/9 + 1/10 - 1/12 + ...
%F Equals 1 - A275712. - _Jon E. Schoenfield_, Nov 11 2016
%e 0.15186778812301...
%Y Cf. A078437, A002808, A085548, A242301, A275712.
%K nonn,cons,more
%O 0,2
%A _Terry D. Grant_, Jul 11 2016
%E Corrected by _Jon E. Schoenfield_, Nov 05 2016
%E Several dubious programs deleted by _N. J. A. Sloane_, Nov 07 2016
%E a(12)-a(13) from _Robert Price_, Nov 14 2016