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%I #14 Sep 29 2020 02:47:08
%S 0,0,1,1,4,6,13,19,41,54,110,157,277,394,706,970,1691,2376,3905,5494,
%T 9130,12355,20262,28146,44316,61761,98023,132891,207912,285667,440118,
%U 604322,929737,1252232,1921062,2625852,3933025,5351483,8085728,10856110
%N Number of subsets of {1, ..., n} that are sum-free but not double-free.
%H Fausto A. C. Cariboni, <a href="/A088811/b088811.txt">Table of n, a(n) for n = 0..75</a>
%H Eric Weisstein's World of Mathematics, <a href="http://mathworld.wolfram.com/Double-FreeSet.html">Double-Free Set</a>
%H Eric Weisstein's World of Mathematics, <a href="http://mathworld.wolfram.com/Sum-FreeSet.html">Sum-Free Set</a>
%H Reinhard Zumkeller, <a href="/A088808/a088808.txt">Illustration of initial terms</a>
%F a(n) = A088808(n) - A088812(n) = A085489(n) - A007865(n).
%K nonn
%O 0,5
%A _Reinhard Zumkeller_, Oct 19 2003
%E Terms a(28) and beyond from _Fausto A. C. Cariboni_, Sep 28 2020