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%I #21 Jun 08 2019 01:16:10
%S 7,790,749896,1270073831726,3264508855407706377676178,
%T 18710490702451568752627532846550947209438603938993
%N Alternating Egyptian fraction expansion of Pi-3.
%C The next term has 99 digits.
%H <a href="/index/Ed#Egypt">Index entries for sequences related to Egyptian fractions</a>
%F Pi -3 = Sum_{k>=1} (-1)^(k+1)/a(k) = 0.14159...; a(n) = (-1)^(n+1)*u(n) where u(1)=7, u(n) = trunc(1/(Pi - 3 - Sum_{k=1..n-1} 1/u(k))) and trunc(x) = floor(x) if x >= 0, trunc(x) = ceiling(x) if x < 0.
%e 1/(Pi - 3 - 1/7 + 1/790) = 749896.4427... hence a(3)=749896.
%K nonn
%O 1,1
%A _Simon Plouffe_
%E Title correction by _Stanislav Sykora_, May 05 2012
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