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%I M4464 N1893 #27 Mar 07 2015 11:55:54
%S 1,1,1,7,-791,-3748629,151648960887729,
%T -1323497544567561138595307148089,
%U 41444465282455711991644958522615049159671653083333293470875123
%N Denominators of an expansion for Pi.
%D N. J. A. Sloane, A Handbook of Integer Sequences, Academic Press, 1973 (includes this sequence).
%D N. J. A. Sloane and Simon Plouffe, The Encyclopedia of Integer Sequences, Academic Press, 1995 (includes this sequence).
%H Mohammad K. Azarian, <a href="http://www.jstor.org/stable/27646572">An Expression for Pi, Problem #870</a>, College Mathematics Journal, Vol. 39, No. 1, January 2008, p. 66. <a href="http://www.jstor.org/stable/27646723">Solution</a> appeared in Vol. 40, No. 1, January 2009, pp. 62-64.
%H H. E. Salzer, <a href="http://www.jstor.org/stable/2305906">The approximation of numbers as sums of reciprocals</a>, Amer. Math. Monthly, 54 (1947), 135-142.
%H J. W. Wrench, Jr., <a href="/A001466/a001466.png">Letter to N. J. A. Sloane, Mar 27 1974</a>
%H <a href="/index/Ph#Pi314">Index entries for sequences related to the number Pi</a>
%F Numerators are 1.
%e a(4) = -791 since Pi - (1/1) - (1/1) - (1/1) - (1/7) = -0.001264489... is closer to 1/(-791) = -0.001264222... than to 1/(-790) = -0.0012658228...
%o (PARI) x=Pi; for(k=0,8,if(x<1,d=round(1/x),d=1); x=x-1/d; print(d,", ")) \\ _Jaume Oliver Lafont_, Feb 21 2009
%Y Cf. A001466, A014013, A073422.
%K sign,frac
%O 0,4
%A _N. J. A. Sloane_
%E Edited by _Henry Bottomley_, Jul 30 2002
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