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 A112837 Large-number statistic from the enumeration of domino tilings of a 5-pillow of order n. 2

%I

%S 1,1,1,1,2,3,7,12,35,87,348,1107,5518,22464,150574,817057,7118856,

%T 49644383,560434040,5142118400,76370120248,914476059335,

%U 17638655014128,274908897964359,6936239946318204,141510942505315328

%N Large-number statistic from the enumeration of domino tilings of a 5-pillow of order n.

%C A 5-pillow is a generalized Aztec pillow. The 5-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 5 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 5-pillow of order 6 is 1666=7^2*34. A112837(n)=7.

%Y A112833 breaks down as A112834^2 times A112835, where A112835 is not necessarily squarefree.

%Y 3-pillows: A112833-A112835; 7-pillows: A112839-A112841; 9-pillows: A112842-A112844.

%K nonn

%O 0,5

%A Christopher Hanusa (chanusa(AT)math.binghamton.edu), Sep 21 2005

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Last modified September 27 07:44 EDT 2021. Contains 347673 sequences. (Running on oeis4.)