By William J. Idsardi, Juan Uriagereka
Languages with stress group syllables into metrical feet (Halle and Idsardi 1995,
Hayes 1995)—non-exhaustive groups of contiguous syllables. The size of feet in
natural languages ranges from unary (a single syllable) to unbounded (as many
syllables as possible); in addition syllables can also remain unfooted. Under these
conditions, the number of possible metrical footings for a string of n syllables is
known to be Fib(2n) (Idsardi 2008), where Fib(n) is the Fibonacci sequence, as in
(1)1 where the nth element is the sum of the previous two elements (for example,
13 = 8 + 5).