%I #43 Jun 21 2022 11:06:49
%S 0,6,6,12,12,6,12,6,12,12,12,12,18,12,12,6,12,12,12,12,24,12,6,12,12,
%T 12,6,12,12,24,12,12,12,12,12,18,12,12,12,12,18,12,12,12,24,12,12,12,
%U 12,24,6,24,12,12,12,12,6,12,24,12,12,12,12,12,12,12,24,12,18
%N Number of vertices of a hexagonal tessellation that lie on subsequent circles centered at the center of one hexagon.
%C Radii of these circles are square roots of A202822.
%C This is A217219 with zeros dropped, except for a(0). - _Andrey Zabolotskiy_, Jun 21 2022
%H Szymon Lukaszyk, <a href="https://github.com/szluk/Graphene/blob/main/gr_circles.m">MATLAB script</a>
%H Szymon Lukaszyk, <a href="https://www.researchgate.net/publication/345982332_A_short_note_about_the_geometry_of_graphene">A short note about the geometry of graphene</a>, ResearchGate, (2020).
%H Szymon Lukaszyk, <a href="/A338992/a338992_1.pdf">Illustration of the subsequent 36 radii around a hex center</a>.
%Y Cf. A202822, A217219, A338947 (similar but with circles centered at a vertex of one hexagon).
%K nonn
%O 0,2
%A _Szymon Lukaszyk_, Nov 17 2020