%I #6 Feb 02 2014 10:59:54
%S 0,2,0,16,0,720,0,35712,0,3628800,0
%N Number of irregular spiral (expanded spiral) appearing with n center points.
%C See A236535 for construction rule.
%C Conjecture: (1) For even n; except n mod 4 = 0; all forms are expanded spirals and equal to n!. (2) For n mod 4 = 0, there are both non-expanded loops and expanded spirals.
%H Kival Ngaokrajang, <a href="/A236755/a236755.pdf">Illustration of irregular spirals, center points = 1..6</a>
%H Kival Ngaokrajang, <a href="/A236755/a236755.txt">Small Basic program</a>
%Y Cf. A014105 (2 center points); A234902, A234903, A234904, A236535 (3 center points); A235088, A235089 (4 center points); A236326, A236327 (5 center points).
%K nonn,more
%O 1,2
%A _Kival Ngaokrajang_, Jan 30 2014
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