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A165397 Number of slanted 5Xn (i=1..5)X(j=i..n+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

%S 7,40,2467,18900,174197,1357468,9996371,68364692,445699471,2796474838,

%T 16994094852

%N Number of slanted 5Xn (i=1..5)X(j=i..n+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 Some solutions for n=3

%e ...1.1.2...........1.1.2...........1.1.2...........1.1.2........

%e .....1.2.2...........1.1.1...........1.2.2...........1.1.1......

%e .......2.2.2...........1.1.1...........2.3.3...........1.1.1....

%e .........4.4.4...........3.3.3...........3.3.4...........3.3.4..

%e ...........3.4.4...........3.3.4...........3.4.4...........3.4.4

%e ------

%e ...1.1.2...........1.2.2...........1.2.2...........1.1.2........

%e .....1.1.1...........2.2.2...........2.2.2...........1.2.2......

%e .......1.4.4...........3.3.3...........4.4.4...........3.3.3....

%e .........4.4.4...........3.3.4...........4.4.4...........3.3.4..

%e ...........3.4.4...........3.4.4...........3.4.4...........3.4.4

%e ------

%e ...1.1.2...........1.1.2...........1.1.2...........1.2.2........

%e .....1.2.2...........1.2.4...........1.1.4...........2.2.4......

%e .......2.2.3...........2.4.4...........1.4.4...........2.4.4....

%e .........3.3.4...........4.4.4...........4.4.4...........4.4.4..

%e ...........3.4.4...........3.4.4...........3.4.4...........3.4.4

%K nonn

%O 2,1

%A _R. H. Hardin_ Sep 17 2009

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Last modified May 24 18:27 EDT 2022. Contains 354043 sequences. (Running on oeis4.)