The top center of this 1-7 X4 Seed Onion dome is made of four (4) pairs of #1 & #7 mogharnas tiles. (See images.) The expanded version of this dome moves opposite pairs of domes pieces, each made up of dozens of the sixteen (16) muqarnas tile types. This results in four ‘ridged’ or ‘accordion’ folded connecting regions in the expanded tiers.
Specification
Animation
FHD – 1920 X 1080p
Symmetry Group [SG]
32-fold, 16 tiles
Symmetry of Form
4-fold
Form Group
Onion Dome
Seed
(1-7)X4 – On this page.
Arrangement
Yes
Motif(s)
No
Motif(s) Angle(s)
NA
Number of Tiers
2 (1), 1 (4), 0 (12)
SG – Tiles Used
All: 1 – 16
Edge Type
Curved, 60° arc with top tangent to plan view plane
Date: 10/12/2014

Arrangements versus Motifs

Here I distinguish between an arrangement and a motif.

Motifs

A motif is the division of the top dome or onion dome into N vertically adjacent mogharnas tile sets using only one tile at each level of the dome. These are translated vertically and horizontally to provide a reliable framework/method of adding tiers to the dome without introducing gaps or overlaps.

Arrangements

An arrangement is the division of the top dome or onion dome into two or more pairs of mogharnas tile groups. Each group may have multiple tiles at the same vertical level, or none. These tile groups are also translated vertically and horizontally to provide another reliable method of adding tiers to the dome without introducing gaps or overlaps.
This arrangement expansion approach can also be seen in the symmetry family of mogharnas domes which can be seen here.

Seed of Onion Dome Arrangement
1-7 X4 Seed of Onion Dome

One (1) = 11.25°
1-7 X4 Seed
(360º/32) X 1 = 11.25º

Seven (7) = 78.75°
1-7 X4 Seed
(360º/32) X 7 = 78.75º

(1 + 7) X 4 X 11.25º = 360º

1-7 X4 Central Onion Dome
1-7 X4 Central Onion Dome