A heptagonal number is a figurate number that represents a heptagon. The most familiar enneahedra are the octagonal pyramid and the heptagonal prism. The circumcenter and the Fermat points of a heptagonal triangle form an equilateral triangle. Plain parathas can be round, heptagonal, square, or triangular. The space between the eight rooms was filled with heptagonal chapels with a triangular apse. If an heptagonal bipyramid is to be face-transitive, all faces must be isosceles triangles. Five times a heptagonal number, plus 1 equals a triangular number. The 17th-century Jacobean pulpit is an unusual heptagonal design. A centered heptagonal prime is a centered heptagonal number that is prime. In geometry, the heptagonal tiling is a regular tiling of the hyperbolic plane. The main body of the twelve-sided shape, contained a heptagonal baptismal font. Harris concluded his collegiate career with a total of eight Ivy League/Heptagonal individual championships. Similar constraints exist if the fullerene has heptagonal (seven-atom) cycles. Thirty-four is a heptagonal number. In architecture, heptagonal floor plans are very rare.