The length of the first two iterations of the construction of the von Koch curve [La longueur des deux premières itérations de la construction de la courbe de von Koch].

                    Iteration= 0        Length=  1          |*
                    Iteration= 1        Length=  1.333      |*
                    Iteration= 2        Length=  1.777      |*
                    Iteration= 3        Length=  2.370      |-*
                    Iteration= 4        Length=  3.160      |--*
                    Iteration= 5        Length=  4.213      |---*
                    Iteration= 6        Length=  5.618      |----*
                    Iteration= 7        Length=  7.491      |------*
                    Iteration= 8        Length=  9.988      |---------*
                    Iteration= 9        Length= 13.318      |------------*
                    Iteration=10        Length= 17.757      |-----------------*
                    Iteration=11        Length= 23.677      |-----------------------*
                    Iteration=12        Length= 31.569      |-------------------------------*
                    Iteration=13        Length= 42.092      |-----------------------------------------*
                    Iteration=14        Length= 56.123      |-------------------------------------------------------*
                    Iteration=15        Length= 74.830      |--------------------------------------------------------------------------*
                    Iteration=16        Length= 99.774      |----------------------------------------------------------------------------------------------------*
                    Iteration=17        Length=133.033      |-------------------------------------------------------------------------------------------------------------------------------------*
                    Iteration=18        Length=177.377      |----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------*
                    Iteration=19        Length=236.503      |-----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------*

See the construction process of the von Koch curve.