ffs ( n -- S(n) )


Vocabulary
rosetta-code.hofstadter-ffs

Inputs
nan object


Outputs
S(n)an object


Definition
USING: kernel math namespaces sequences ;

IN: rosetta-code.hofstadter-ffs

: ffs ( n -- S(n) ) dup S get length - inc-SR 1 - S get nth ;