%N Number of polyfetts (or polifetti) with n cells, identifying mirror images.
%C A polyfett is a generalized polyabolo (or polytan). Its cells are equal isosceles right triangles on the quadrille grid, which may be joined along equal edges or at vertices.
%C Polyfetts are to polyaboloes what polyplets (or polykings) are to polyominoes.
%H Sean A. Irvine, <a href="https://github.com/archmageirvine/joeis/blob/master/src/irvine/oeis/a337/A337867.java">Java program</a> (github)
%H George Sicherman, <a href="https://userpages.monmouth.com/~colonel/polyfetts/index.html">Catalogue of Polyfetts</a>
%H George Sicherman, <a href="/A337867/a337867_1.c.txt">polyaboloes.c</a>
%e For n = 2, a(2) = 10. Two polyabolo cells can be joined at edges to form 3 different diaboloes, or at corners to form 7 different proper difetts.
%o See link to Unix C program polyaboloes.c under LINKS.
%Y Cf. A006074.
%A _George Sicherman_, Sep 27 2020