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A071097 Number of ways to tile Aztec diamond of order n with 2 squares removed with dominoes. 0
2, 8, 160, 4608, 393216, 37748736, 11022630912, 5315022028800, 6333186975989760, 10808639105689190400, 48595641419178600038400, 381803330140010815527321600, 6932464219998129539435095654400 (list; graph; refs; listen; history; text; internal format)
OFFSET

2,1

REFERENCES

J. Propp, Enumeration of matchings: problems and progress, pp. 255-291 in L. J. Billera et al., eds, New Perspectives in Algebraic Combinatorics, Cambridge, 1999 (see Problem 7).

LINKS

Table of n, a(n) for n=2..14.

J. Propp, Updated article

J. Propp, Enumeration of matchings: problems and progress, in L. J. Billera et al. (eds.), New Perspectives in Algebraic Combinatorics

EXAMPLE

From Andrew Howroyd, Mar 07 2016: (Start)

The 2 removed squares are central and separated by a knights move.

Illustration of n = 4:

*            ++

*           ++++

*          ++++++

*         +++++ ++

*         +++ ++++

*          ++++++

*           ++++

*            ++

(End)

CROSSREFS

Sequence in context: A012571 A018926 A012432 * A012537 A012540 A175538

Adjacent sequences:  A071094 A071095 A071096 * A071098 A071099 A071100

KEYWORD

nonn

AUTHOR

N. J. A. Sloane, May 28 2002

EXTENSIONS

a(11)-a(14) from Andrew Howroyd, Mar 07 2016

STATUS

approved

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Last modified June 4 03:40 EDT 2020. Contains 334815 sequences. (Running on oeis4.)