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%I #20 May 14 2022 04:55:19
%S 2,8,28,116,474,2001,8508,37162,163730,729683,3269602,14773831
%N Number of one-sided polydrafters with n cells.
%C A polydrafter is a plane figure formed by joining equal triangles with angles of 30, 60, and 90 degrees with certain restrictions on how they are joined. See A056842 for details. One-sided means that distinct mirror images are counted separately.
%C For odd n, an n-drafter cannot have mirror symmetry, so odd entries in this sequence are double those in A056842.
%D Ed Pegg, Jr., Polyform puzzles, in Tribute to a Mathemagician, Peters, 2005, pp. 119-125.
%H K. Ishino, <a href="http://puzzlewillbeplayed.com/Polydrafters/">Polydrafters</a>
%H Bernd Karl Rennhak, <a href="http://www.logelium.de/Drafter/PolyDrafter_EN.htm">Drafter</a>
%e There are 6 two-sided didrafters, two have distinct mirror images, so there are 8 one-sided didrafters. Thus a(2) = 8.
%Y Cf. A056842 (number of two-sided polydrafters).
%K nonn,more
%O 1,1
%A _George Sicherman_, Mar 21 2013
%E a(8)-a(12) from _Aaron N. Siegel_, May 13 2022
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