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%I #7 Mar 21 2016 08:18:25
%S 0,1,5,19,59,161,405,967,2231,5029,11153,24443,53091,114505,245549,
%T 524047,1113839,2358989,4980393,10485379,22019675,46136881,96468485,
%U 201326039,419429799,872414581,1811938625,3758095627,7784627411
%N Sequence arising from enumeration of domino tilings of Aztec Pillow-like regions.
%C Differences give A066368.
%D 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 13).
%H J. Propp, <a href="http://faculty.uml.edu/jpropp/articles.html">Publications and Preprints</a>
%H J. Propp, Enumeration of matchings: problems and progress, in L. J. Billera et al. (eds.), <a href="http://www.msri.org/publications/books/Book38/contents.html">New Perspectives in Algebraic Combinatorics</a>
%H <a href="/index/Rec#order_05">Index entries for linear recurrences with constant coefficients</a>, signature (7,-19,25,-16,4).
%F a(n)=(n+1)(2^n-1)-n^2.
%F G.f.:(x*(4*x^3-3*x^2+2*x-1))/((2*x-1)^2*(x-1)^3) [From Maksym Voznyy (voznyy(AT)mail.ru), Jul 26 2009]
%e a(3)=4(2^3-1)-3^2=19.
%Y Cf. A092437-A092443.
%K easy,nonn
%O 0,3
%A Christopher Hanusa (chanusa(AT)math.washington.edu), Mar 24 2004
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