This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.
%I A192091 #23 Jan 01 2023 09:47:25 %S A192091 1,8,68,90,126,178,325,584,1165,2030,3619,6080,10987,19362,35477, %T A192091 62360,111837,195614,350707,619568,1112315,1967090,3514597,6214984, %U A192091 11093549,19664558,35090115,62247552,110934699,196859394,350650261 %N A192091 Number of tatami tilings of a 5 X n grid (with monomers allowed). %C A192091 A tatami tiling consists of dimers (1 X 2) and monomers (1 X 1) where no four meet at a point. %H A192091 A. Erickson, F. Ruskey, M. Schurch and J. Woodcock, <a href="https://doi.org/10.37236/596">Monomer-Dimer Tatami Tilings of Rectangular Regions</a>, Electronic Journal of Combinatorics, 18(1) (2011) P109, 24 pages. %e A192091 Here are some tatami tilings of the 5 X 3 grid: %e A192091 _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ %e A192091 |_ _| |_| | |_| |_|_ _| | |_ _| |_| |_| | |_ _| %e A192091 |_ _|_| |_| | |_|_ _| | |_| |_|_| | | |_|_| | | %e A192091 |_|_ _|_|_| |_|_ _|_|_| |_|_|_ _|_| |_|_ _|_|_| %Y A192091 Cf. A192090, A192092, A033508 (without tatami condition). Row sums of A272474. %K A192091 nonn %O A192091 0,2 %A A192091 _Frank Ruskey_ and Yuji Yamauchi (eugene.uti(AT)gmail.com), Jul 07 2011