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%I #41 May 14 2022 11:22:55
%S 1,0,0,2,0,3,4,4,6,5,8,6,6,7,8,7
%N Side length of the smallest equilateral triangles that have a separated dissection into n equilateral triangles with integer sides, or 0 if no such triangle exists.
%C No solution exists for n = [2, 3, 5].
%C The meaning of "separated dissection" is defined at the end of the introduction of the Drapal and Hamalainen article, see link. - _Hugo Pfoertner_, Feb 17 2018
%H Stuart Anderson, <a href="http://web.archive.org/web/20170806090944/http://www.squaring.net/tri/tritri/tet.html">An Introduction to Triangled Equilateral Triangles</a>
%H Ales Drapal and Carlo Hamalainen, <a href="http://arxiv.org/abs/0910.5199">An enumeration of equilateral triangle dissections</a>, arXiv:0910.5199 [math.CO], 2009-2010.
%H Hugo Pfoertner, <a href="/A290820/a290820.pdf">Illustration for a(16)=7.</a>
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%e a(7) = 4:
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%e a(8) = 4:
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%e a(9) = 6:
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%e a(10) = 5:
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%e a(11) = 8:
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%e a(12) = 6:
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%e a(13) = 6:
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%e a(14) = 7:
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%e a(15) = 8:
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%e a(16) = 7:
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%Y Cf. A167123, A290653, A290697, A290821, A300001.
%K nonn,more
%O 1,4
%A _Hugo Pfoertner_, Aug 11 2017
%E Title changed as suggested by _Peter Munn_, Feb 17 2018
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