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%I #16 Jun 05 2017 02:09:19
%S 0,1,1,1,7,1,2,43,43,2,3,277,969,277,3,5,1777,23663,23663,1777,5,8,
%T 11407,571099,2180738,571099,11407,8,13,73219,13807469,198906617,
%U 198906617,13807469,73219,13,21,469981,333735575,18169793971,68534828391,18169793971,333735575,469981,21
%N Array read by antidiagonals: T(m,n) = number of edge covers in the grid graph P_m X P_n.
%H Andrew Howroyd, <a href="/A286912/b286912.txt">Table of n, a(n) for n = 1..276</a>
%H Eric Weisstein's World of Mathematics, <a href="http://mathworld.wolfram.com/EdgeCover.html">Edge Cover</a>
%H Eric Weisstein's World of Mathematics, <a href="http://mathworld.wolfram.com/GridGraph.html">Grid Graph</a>
%e Table starts:
%e ======================================================================
%e m\n| 1 2 3 4 5 6
%e ---|------------------------------------------------------------------
%e 1 | 0 1 1 2 3 5 ...
%e 2 | 1 7 43 277 1777 11407 ...
%e 3 | 1 43 969 23663 571099 13807469 ...
%e 4 | 2 277 23663 2180738 198906617 18169793971 ...
%e 5 | 3 1777 571099 198906617 68534828391 23650967140325 ...
%e 6 | 5 11407 13807469 18169793971 23650967140325 30833670159649637 ...
%e ...
%Y Rows 1-3 are A000045(n-1), A286911, A288031.
%Y Main diagonal is A286913.
%Y Cf. A210662, A099390, A089934, A218354.
%K nonn,tabl
%O 1,5
%A _Andrew Howroyd_, May 15 2017
%E T(1,1) corrected by _Andrew Howroyd_, Jun 04 2017
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