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%I #15 Sep 15 2017 06:12:31
%S 1,2,3,5,8,14,26,46,83,151,276,503,921,1689,3113,5730,10549,19441,
%T 35868,66209,122316,226157,418373,774394,1434130,2657246,4925837,
%U 9135444,16949660,31460444,58415377,108502932,201604081,374708242,696650259,1295562800,2410001851,4484208954,8345621293
%N Number of subsets of {1,2,...,n} with the sum of reciprocals <= 1.
%C The number of distinct sums of reciprocals is given by A212607.
%C a(n) grows as 2^(b*n) with b=0.911... (Tikhomirov et al. 2017).
%H Robert Gerbicz, <a href="/A212657/b212657.txt">Table of n, a(n) for n = 0..95</a>
%H M. Tikhomirov et al., <a href="https://mathoverflow.net/q/281124">Sets of unit fractions with sum <=1</a>, MathOverflow, 2017.
%o (PARI) { A212657(n) = my(L=lcm(vector(n,i,i))); polcoeff( prod(i=1,n, 1+x^(L/i)+O(x^(L+1)) )/(1-x), L); }
%Y Cf. A212658 (reciprocals can appear multiple times).
%Y Cf. A212606, A212607, A020473, A092669, A092671, A208480.
%K nonn
%O 0,2
%A _Max Alekseyev_, May 23 2012
%E a(32)-a(35) from _Alois P. Heinz_, May 23 2012
%E a(36)-a(95) from _Robert Gerbicz_, May 23 2012
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