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%I #5 Apr 25 2015 21:43:51
%S 1,1,1,2,1,1,5,6,6,1,1,5,13,26,30,20,1,1,5,13,41,90,140,140,70,1,1,5,
%T 13,41,121,302,560,742,630,252
%N Triangle read by rows, arising from enumeration of domino tilings of Aztec Pillow-like regions.
%C The rows are of lengths 1, 3, 5, 7, ...
%C In particular, the rows are 1; 1,1,2; 1,1,5,6,6; 1,1,5,13,26,30,20; ... etc.
%C Call the first row row 0 and entries starting from 0. Then entries i=0 through k in row k are A046717(i).
%C In row k, entry k+1 is sequence A092438 and entry k+2 is sequence A092439.
%C In row k, entry 2k-1 is A002457(k-1) and entry 2k is A000984(k).
%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>
%Y Cf. A092438-A092443.
%K hard,nonn,tabf
%O 0,4
%A Christopher Hanusa (chanusa(AT)math.washington.edu), Mar 24 2004
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