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%I #3 Aug 24 2012 10:50:01
%S 2,2,2,2,2,5,59,751,894503,18292510297,5993565343364843081,
%T 818638308229506590060391447618925613,
%U 5089762493052274984454740075748133007549187136115352857668628331136557
%N Denominators of an Egyptian fraction for "e", using only prime numbers and allowing repetitions.
%e 1/2+1/2+1/2+1/2 = 2 (integer part of "e").
%e 1/2+1/5+1/59+1/751 gives an approximation that is good to 10 decimal digits.
%e Adding the other fractions we get approximations good to 18, 35, 69, 137, 272, 541 decimal digits.
%p P:=proc(n) local a,i; a:=evalf(exp(1)-2,100); for i from 1 by 1 to 4 do print(2); od; for i from 1 by 1 to n do if 1/ithprime(i)<a then a:=a-1/ithprime(i); print(a); print(ithprime(i)); fi; od; end: P(100000);
%Y Cf. A139514, A139515, A139517-A139523.
%K easy,nonn
%O 0,1
%A _Paolo P. Lava_ and _Giorgio Balzarotti_, Apr 24 2008
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