

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. 255291 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



