Enneagrammic crossed-antiprism
Encyclopedia
In geometry
, the enneagrammic crossed-antiprism is one in an infinite set of nonconvex antiprisms formed by triangle sides and two regular star polygon caps, in this case two {9/4} enneagrams
.
It differs from the enneagrammic antiprism (9/4) by having opposite orientations on the two enneagrams.
Geometry
Geometry arose as the field of knowledge dealing with spatial relationships. Geometry was one of the two fields of pre-modern mathematics, the other being the study of numbers ....
, the enneagrammic crossed-antiprism is one in an infinite set of nonconvex antiprisms formed by triangle sides and two regular star polygon caps, in this case two {9/4} enneagrams
Enneagram (geometry)
In geometry, an enneagram is a nine-pointed geometric figure. It is sometimes called a nonagram.-Regular enneagram:A regular enneagram is constructed using the same points as the regular enneagon but connected in fixed steps...
.
It differs from the enneagrammic antiprism (9/4) by having opposite orientations on the two enneagrams.