Articles on Convex Shapes, Tangrams, and Similar Puzzle Pieces

These are nice reading (at various levels of difficulty) if you enjoy playing with the "Convexity" puzzle.
  1. Convex Tangrams (Scott, Australian Mathematics Teacher, 2006)

    2. This is a nice, readable account of classifying the convex tangram shapes. It is a simplification and clarification of the older article by Wang and Hsiung below.

  2. A Theorem on the Tangram (Wang and Hsiung, American Mathematical Monthly, 1942)

    3. This is the original article that determined the number of convex tangrams. The mathematics is not advanced, but it's a challenging read, with a lot of leaps left to the reader to figure out.

  3. The Convex Configurations of “Sei Shonagon Chie no Ita,” Tangram, and Other Silhouette Puzzles with Seven Pieces

    The authors look at a set of Japanese puzzle pieces similar to the tangram set, which can generate more convex shapes. They also look for optimal sets of "tangram-like" pieces which generate as many convex shapes as possible.

  4. On the Multiplicity of Polyabolos and Tangrams with Four-Fold Symmetry (Durian, Mathematics Magazine, 2021)

    5. Studies configurations of tangram pieces with special symmetries, and proves that there are only two configurations with 4-fold rotational symmetry.

  5. Tangrams, Part 1 and Part 2 (Martin Gardner)

    6. Two articles from Scientific American, as reprinted in Wheels, Life, and Other Amusements. A nice mix of history, background, problems to play with, and mathematical analysis.