This work is a composition of spirals of equilateral triangles with
side lengths which follow the Padovan sequence, a sequence of
integers P(n) defined by the initial values P(0)=P(1)=P(2)=1 and
the recurrent relation P(n)=P(n-3)+P(n-2). The first few values of
P(n) are then 1, 1, 1, 2, 2, 3, 4, 5, 7, 9, 12, ...
The spiral pattern constructed in this way is replicated along the
vertical axis and scaled to fit in the concavity of each successive
replication. It's interesting to note that, by using only one type of
triangle and a suitable gray graduation, an intriguing perceptual ambiguity is attained.