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Number of ways to reciprocally link elements of an nX6 array either to themselves or to exactly two king-move neighbors, without 3-loops
1

%I #4 Dec 17 2012 10:57:21

%S 1,1441,816159,389859889,179768901595,85240331175084,

%T 40274546959211319,19024400007896312662,8986807181301920000278,

%U 4245342275704299946914591,2005473806376394839453915403,947373651435473076102298469864

%N Number of ways to reciprocally link elements of an nX6 array either to themselves or to exactly two king-move neighbors, without 3-loops

%C Column 6 of A220652

%H R. H. Hardin, <a href="/A220651/b220651.txt">Table of n, a(n) for n = 1..38</a>

%e Some solutions for n=3 0=self 1=nw 2=n 3=ne 4=w 6=e 7=sw 8=s 9=se (reciprocal directions total 10)

%e .00.67.46.48.69.47...00.00.00.78.68.48...00.69.46.49.69.47...00.00.78.00.79.00

%e .36.48.00.28.39.17...00.00.39.27.28.28...00.79.16.48.13.17...00.38.26.34.00.17

%e .00.26.46.24.36.14...00.00.36.14.26.24...36.46.14.26.34.00...00.26.46.46.34.00

%K nonn

%O 1,2

%A _R. H. Hardin_ Dec 17 2012