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Number of slanted nX7 (i=1..n)X(j=i..7+i-1) 1..4 arrays with all 1s connected, all 2s connected, all 3s connected, all 4s connected, 1 in the upper left corner, 2 in the upper right corner, 3 in the lower left corner, 4 in the lower right corner, and with no element having more than 3 neighbors with the same value
0

%I #3 Mar 31 2012 12:35:35

%S 481,18912,196082,1357468,7051772,30346872,113675050,385459632,

%T 1210822319,3585582454,10137294012

%N Number of slanted nX7 (i=1..n)X(j=i..7+i-1) 1..4 arrays with all 1s connected, all 2s connected, all 3s connected, all 4s connected, 1 in the upper left corner, 2 in the upper right corner, 3 in the lower left corner, 4 in the lower right corner, and with no element having more than 3 neighbors with the same value

%e One solution for n=6

%e ...1.1.2.2.2.2.2..........

%e .....1.1.2.3.2.2.2........

%e .......1.3.3.2.3.2.2......

%e .........3.3.2.3.3.4.4....

%e ...........3.3.3.3.3.4.4..

%e .............3.4.4.4.4.4.4

%K nonn

%O 2,1

%A _R. H. Hardin_ Sep 17 2009