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%I #18 Nov 03 2023 17:02:16
%S 1,4,3,4,5,6
%N Maximal number of right angles in an n-gon.
%C A proper definition is needed for this sequence.
%C Conjecture from _R. J. Mathar_, Mar 07 2008, Apr 21 2008: (Start)
%C The correct sequence is a(n)=A014681(n-1), because a polyomino with a zigzag "stair" shape along a diagonal provides a solution where the number of right angles equals the number of edges:
%C ┌─────────┐
%C |. . . . .|
%C | ┘
%C |. . . . .
%C |
%C |. .|
%C | ┌─┘
%C |.|
%C └─┘
%C (End)
%C Possibly an incorrect version of A049008. - _Michal Paulovic_, Sep 27 2023
%e The first (n=3) integer in this sequence is 1 because a triangle cannot have more than one right angle.
%Y Cf. A049008.
%K nonn,more,uned,obsc
%O 3,2
%A Asher Stuhlman (asherstuhlman(AT)gmail.com), Nov 06 2007