A polyfett [polifetto] is a generalized polyabolo [polytan]. It is formed by joining isosceles right triangles on the quadrille grid along edges and at corners.
Table of n, a(n) for n=1..8.
George Sicherman, Catalogue of Polyfetts
For n=2 there are 4 diaboloes and 11 proper difetts, distinguishing mirror images. See the link.
Cf. A337867 (number of polyfetts with n cells, identifying mirror images).
Sequence in context: A036734 A201041 A201551 * A240276 A206600 A016172
Adjacent sequences: A339767 A339768 A339769 * A339771 A339772 A339773
George Sicherman, Dec 16 2020