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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. 2

%I

%S 0,0,2,16,352,240,107520,1032837120

%N 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 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 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 Fausto A. C. Cariboni, <a href="/A289972/a289972.txt">Complete solutions for a(3)-a(6)</a>

%H Fausto A. C. Cariboni, <a href="/A289972/a289972_1.txt">Complete solutions for a(7)</a>

%Y Cf. A089676.

%K nonn,hard,more

%O 1,3

%A _Fausto A. C. Cariboni_, Jul 16 2017

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Last modified March 22 12:46 EDT 2019. Contains 321421 sequences. (Running on oeis4.)