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%I #26 Nov 15 2023 17:40:14
%S 1,1,1,1,1,1,1,1,1,6,13,22,64,114,172,242,320,406,561,811,1188,2204,
%T 4093,7181,13185,22687,36597,56934,85897,126485,189500,290730,453035,
%U 739070,1234480,2061104,3452517,5710991,9253861,14755851,23232374,36208272,56484574
%N Number of tilings of a 12 X n rectangle using 2*n copies of the disconnected shape [ooo___ooo].
%H Alois P. Heinz, <a href="/A323423/b323423.txt">Table of n, a(n) for n = 0..4893</a>
%H D. E. Knuth, <a href="https://www.youtube.com/watch?v=_cR9zDlvP88">Dancing Links</a>, 24th Annual Christmas Lecture, Stanfordonline video (2018)
%H D. E. Knuth, <a href="https://arxiv.org/abs/cs/0011047">Dancing Links</a>, arXiv:cs/0011047 [cs.DS], 2000.
%H Vaclav Kotesovec, <a href="/A323423/a323423.txt">G.f. for A323423</a>
%H Wikipedia, <a href="https://en.wikipedia.org/wiki/Dancing_Links">Dancing Links</a>
%F a(n) ~ c * d^n, where d = 1.6015104441944202301254108408823287548000767754983674455370068394906003425... and c = 0.146413500304969675060082381912654288970333957537812034040245936... - _Vaclav Kotesovec_, Jan 15 2019
%e a(9) = 6:
%e .
%e ._._._._._._._._._. ._____._._._._____. ._._._._._._._._._.
%e | | | | | | | | | | |_____| | | |_____| | | | | | | | | | |
%e | | | | | | | | | | |_____| | | |_____| | | | | | | | | | |
%e |_|_|_|_|_|_|_|_|_| |_____|_|_|_|_____| |_|_|_|_|_|_|_|_|_|
%e | | | | | | | | | | |_____| | | |_____| |_____| | | |_____|
%e | | | | | | | | | | |_____| | | |_____| |_____| | | |_____|
%e |_|_|_|_|_|_|_|_|_| |_____|_|_|_|_____| |_____|_|_|_|_____|
%e | | | | | | | | | | |_____| | | |_____| | | | | | | | | | |
%e | | | | | | | | | | |_____| | | |_____| | | | | | | | | | |
%e |_|_|_|_|_|_|_|_|_| |_____|_|_|_|_____| |_|_|_|_|_|_|_|_|_|
%e | | | | | | | | | | |_____| | | |_____| |_____| | | |_____|
%e | | | | | | | | | | |_____| | | |_____| |_____| | | |_____|
%e |_|_|_|_|_|_|_|_|_| |_____|_|_|_|_____| |_____|_|_|_|_____|
%e .
%e ._____._._._._____. ._____._._._._____. ._____._._._._____.
%e |_____| | | |_____| |_____| | | |_____| |_____| | | |_____|
%e | | | | | | | | | | |_____| | | |_____| |_____| | | |_____|
%e | | | |_|_|_| | | | | | | |_|_|_| | | | |_____|_|_|_|_____|
%e |_|_|_| | | |_|_|_| | | | | | | | | | | | | | | | | | | | |
%e |_____| | | |_____| |_|_|_| | | |_|_|_| | | | | | | | | | |
%e |_____|_|_|_|_____| |_____|_|_|_|_____| |_|_|_|_|_|_|_|_|_|
%e |_____| | | |_____| |_____| | | |_____| |_____| | | |_____|
%e | | | | | | | | | | |_____| | | |_____| |_____| | | |_____|
%e | | | |_|_|_| | | | | | | |_|_|_| | | | |_____|_|_|_|_____|
%e |_|_|_| | | |_|_|_| | | | | | | | | | | | | | | | | | | | |
%e |_____| | | |_____| |_|_|_| | | |_|_|_| | | | | | | | | | |
%e |_____|_|_|_|_____| |_____|_|_|_|_____| |_|_|_|_|_|_|_|_|_|
%e .
%Y Cf. A320437, A323352, A323483, A322473.
%K nonn,easy
%O 0,10
%A _Alois P. Heinz_, Jan 14 2019