OFFSET
0,3
COMMENTS
The interest comes from a simplest recursion than the cross-recursion, dependent on parity, governing the projections onto the x and y axis.
LINKS
A. Karttunen, Table of n, a(n) for n = 0..65535
FORMULA
Initially, M(0)=0; recursion: M(n+1)=M(n).f(M(n), n).f(M(n), n+1).d(M(n), n); -f(m, n) is the alphabetic morphism i := i+2^n; [example: f(0 1 2 1 2 3 4 3 4 5 6 5 4 3 2 3, 2)=4 5 6 5 6 7 8 7 8 9 10 9 8 7 6 7 ] -d(m, n) is the complementation to 2^(n-1)*3-2, alphabetic morphism; [example: d(0 1 2 1 2 3 4 3 4 5 6 5 4 3 2 3, 3)=10 9 8 9 8 7 6 7 6 5 4 5 6 7 8 7] Here is M(3). [M(1)=0.1.2.1, M(2)=0 1 2 1.2 3 4 3.4 5 6 5.4 3 2 3]
CROSSREFS
KEYWORD
nonn
AUTHOR
Claude Lenormand (claude.lenormand(AT)free.fr), Jan 24 2001
EXTENSIONS
Extended by Antti Karttunen, Aug 01 2009
STATUS
approved