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%I #2 Mar 30 2012 17:23:26
%S 1,4,44,1953,4179942,42836179578838,3958573977160882295479936105,
%T 36328295343356352083453782833218820307659379901717630389
%N Greedy Egyptian fraction expansion for 4/Pi
%C Sum_{n>=0}1/a(n)=4/Pi
%C Truncating the series to three terms yields the convergent 22/7 as an approximation to Pi:
%C 1+1/4+1/44=14/11=4/(22/7)
%H Wikipedia, <a href="http://en.wikipedia.org/wiki/Greedy_algorithm_for_Egyptian_fractions">Greedy algorithm for Egyptian fractions</a>
%o (PARI) x=4/Pi; for (k=0,7,d=ceil(1/x);x=x-1/d;print(d,", "))
%Y Cf. A088538, A154956, A156618.
%K frac,nonn
%O 0,2
%A _Jaume Oliver Lafont_, Feb 24 2009