OFFSET
0,2
LINKS
Steven R. Finch, Substitution dynamics, January 23, 2014. [Cached copy, with permission of the author]
C. Godrèche and J. M. Luck, Quasiperiodicity and randomness in tilings of the plane, J. Statist. Phys. 55 (1989) 1-28.
MATHEMATICA
p[n_] := p[n] = 2 p[n-1] q[n-1] - p[n-1]^2 q[n-2];
q[n_] := 2 p[n] q[n-1] - p[n-1] p[n-2] q[n-1] q[n-2]^2;
p[0] = 1; q[0] = 1; p[1] = 2; q[1] = 4;
CROSSREFS
KEYWORD
nonn
AUTHOR
Steven Finch, Jan 16 2014
STATUS
approved