A235858 Associated with random Penrose-Robinson tilings of the plane.

1, 4, 88, 236544, 211790340292608, 56686233255830734129089579999779880960

Offset: 0

Author

Steven Finch, Jan 16 2014

Keywords

• nonn

Comments

In the Mathematica code, let p=A235857; q=A235858 for convenience.

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.

Crossrefs

Cf. A072042, A235857.

Programs

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;