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.
Table of n, a(n) for n=1..5.
George Sicherman, Catalogue of Polypentagrams
Five different figures can be formed by joining 3 pentagrams, so a(3) = 5.
Cf. A103465, A000105, A000507.
Sequence in context: A062147 A213048 A069321 * A177797 A293717 A186859
Adjacent sequences: A211176 A211177 A211178 * A211180 A211181 A211182
George Sicherman, Feb 01 2013