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%I #4 Jun 01 2010 03:00:00
%S 1,1,1,1,1,2,3,7,11,28,51,154,389,1556,4833,22477,80532,440512,
%T 1916580,13388593,73763989,632754664,4175659899,42606281476,
%U 336819337955,4181786155008,40981322633555,630857431556758,7576627032674784
%N Large-number statistic from the enumeration of domino tilings of a 7-pillow of order n.
%C A 7-pillow is a generalized Aztec pillow. The 7-pillow of order n is a rotationally-symmetric region. It has a 2 X 2n central band of squares and then steps up from this band with steps of 7 horizontal squares to every 1 vertical square and steps down with steps of 1 horizontal square to every 1 vertical square.
%D C. Hanusa (2005). A Gessel-Viennot-Type Method for Cycle Systems with Applications to Aztec Pillows. PhD Thesis. University of Washington, Seattle, USA.
%e The number of domino tilings of the 7-pillow of order 8 is 23353=11^2*193. A112840(n)=11.
%Y A112839 breaks down as A112840^2 times A112841, where A112841 is not necessarily squarefree.
%Y 3-pillows: A112833-A112835; 5-pillows: A112836-A112838; 9-pillows: A112842-A112844.
%K nonn
%O 0,6
%A Christopher Hanusa (chanusa(AT)math.binghamton.edu), Sep 21 2005