%I #24 Apr 26 2023 07:09:33
%S 1,1,5,31,238,2020,17754,160820,1479536,13792972,129839465
%N Number of free polypentagrams with n cells.
%C A polypentagram is a plane figure made of five-pointed stars joined edge to edge. Free means that mirror images are counted as the same polypentagram.
%H George Sicherman, <a href="https://sicherman.net/polypgrams/index.html">Catalogue of Polypentagrams</a>
%e Five different figures can be formed by joining 3 pentagrams, so a(3) = 5.
%Y Cf. A103465, A000105, A000507.
%K nonn,hard,more
%O 1,3
%A _George Sicherman_, Feb 01 2013
%E a(6)-a(11) from _Aaron N. Siegel_, May 23 2022
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