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A289972 Number of sets S (cubic acute n-set), with cardinality A089676(n) >= 3, of points in {0,1}^n in real n-dimensional Euclidean space such that every angle determined by three distinct points in S is acute.

%I A289972 #13 Jun 03 2018 02:01:20
%S A289972 0,0,2,16,352,240,107520,1032837120
%N A289972 Number of sets S (cubic acute n-set), with cardinality A089676(n) >= 3, of points in {0,1}^n in real n-dimensional Euclidean space such that every angle determined by three distinct points in S is acute.
%C A289972 Consider the 2^n points {0,1}^n in real Euclidean space. Then A089676(n) = maximal size of a subset S of these 2^n points such that there is no triple of points P,Q,R in S which subtends a right angle. That is, we are not allowed to have P-Q perpendicular to R-Q. Here we count such sets.
%H A289972 D. Bevan, <a href="http://www.combinatorics.org/ojs/index.php/eljc/article/view/v13i1r12">Sets of Points Determining Only Acute Angles and Some Related Coloring Problems</a>, Electronic J. of Combinatorics, 13(1), 2006, #R12.
%H A289972 Fausto A. C. Cariboni, <a href="/A289972/a289972.txt">Complete solutions for a(3)-a(6)</a>
%H A289972 Fausto A. C. Cariboni, <a href="/A289972/a289972_1.txt">Complete solutions for a(7)</a>
%Y A289972 Cf. A089676.
%K A289972 nonn,hard,more
%O A289972 1,3
%A A289972 _Fausto A. C. Cariboni_, Jul 16 2017