- the
Prime in the 3-aliquot tree. a Wedderburn-Etherington number, an
enneagonal number a
centered triangular number. the
number of
parallelogram polyominoes...
- n-gonal
bipyramid Properties convex,
regular polygon faces, isogonal,
translated bases,
sides ⊥
bases Net Example: net of
uniform enneagonal prism (n = 9)...
- 2016-05-29. "Sloane's A060544 :
Centered 9-gonal (also
known as
nonagonal or
enneagonal) numbers". The On-Line
Encyclopedia of
Integer Sequences. OEIS Foundation...
- A
nonagonal number, or an
enneagonal number, is a
figurate number that
extends the
concept of
triangular and
square numbers to the
nonagon (a nine-sided...
- A
centered nonagonal number (or
centered enneagonal number) is a
centered figurate number that
represents a
nonagon with a dot in the
center and all other...
- 2016-05-30. "Sloane's A060544 :
Centered 9-gonal (also
known as
nonagonal or
enneagonal) numbers". The On-Line
Encyclopedia of
Integer Sequences. OEIS Foundation...
- 2016. "Sloane's A060544 :
Centered 9-gonal (also
known as
nonagonal or
enneagonal) numbers". The On-Line
Encyclopedia of
Integer Sequences. OEIS Foundation...
- n-gonal
trapezohedron Properties convex, vertex-transitive,
regular polygon faces,
congruent &
coaxial bases Net Net of
uniform enneagonal antiprism (n = 9)...
- In geometry, a bipyramid, dipyramid, or
double pyramid is a
polyhedron formed by
fusing two
pyramids together base-to-base. The
polygonal base of each...
- in role
playing games,
known as a d10
Truncated square trapezohedron Enneagonal pyramid (9-pyramid) Ten of
diamonds decahedron - a space-filling polyhedron...
