Triple FJS

[Eric Angelini]

Hello Hugo and Joerg,

[Hugo ]:

> It reminds me of a sequence discussed by Hofstadter [0],
> of the number of triangular numbers between each successive
> pair of squares. I'm not sure, but I think this is A006338
> (...)

... The two sequences differ: (DH stands for D.Hofstadter and
FJ for Fractal Jump):

DH. : 21211212121 1 2121121212 1 121 2 1 12 1 2 1 1 2 ...
FJ. : 21211212121 2 2121121212 2 121 1 2 12 2 1 2 1 1 ...
                  ^            ^     ^ ^    ^ ^ ^   ^ 
-----------

[Joerg]:

> You might want to check A035263 "period-doubling sequence"

... I did but... couldn't see the link -- is there a relation-
ship? If I turn the 1's and 0's of A035263 into 1's and 2's 
of the above FJ (or 2's and 1's), I see no match :-(


FJ. : 21211212121221211212122121121221211 ...
A035. 10111010101110111011101010111010101 ...
0>2   12111212121112111211121212111212121 ...
>2+1  21222121212221222122212121222121212 ...
FJ. : 21211212121221211212122121121221211 ...
        ^^^^^^^^^    ^^^^ ^^    ^ ^^    ^

Best to both of you,
E.