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A235858 Associated with random Penrose-Robinson tilings of the plane. 4
1, 4, 88, 236544, 211790340292608, 56686233255830734129089579999779880960 (list; graph; refs; listen; history; text; internal format)
OFFSET

0,2

COMMENTS

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

LINKS

Table of n, a(n) for n=0..5.

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

Cf. A072042, A235857.

Sequence in context: A195373 A065754 A244013 * A262409 A183880 A220318

Adjacent sequences: A235855 A235856 A235857 * A235859 A235860 A235861

KEYWORD

nonn

AUTHOR

Steven Finch, Jan 16 2014

STATUS

approved

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Last modified December 1 08:20 EST 2022. Contains 358458 sequences. (Running on oeis4.)