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A165396
Number of slanted 4Xn (i=1..4)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
5, 68, 1012, 6412, 37784, 196082, 927564, 4084752, 17038624, 68071813, 262504506, 982898538, 3589650686, 12832470099, 45031577790, 155480658676, 529194130242, 1778374522003, 5908578890738, 19430770840182
OFFSET
2,1
EXAMPLE
Some solutions for n=4
...1.2.2.2.........1.2.2.2.........1.1.1.2.........1.1.1.2......
.....2.2.2.2.........3.3.2.2.........1.2.2.2.........1.1.3.3....
.......3.3.2.2.........3.3.3.4.........2.3.3.4.........1.3.3.3..
.........3.3.3.4.........3.4.4.4.........3.3.4.4.........3.4.4.4
------
...1.1.2.2.........1.1.1.2.........1.3.2.2.........1.4.4.2......
.....3.3.2.2.........2.2.2.2.........3.3.2.2.........4.4.2.4....
.......3.3.3.3.........4.4.4.4.........3.3.2.2.........4.4.4.4..
.........3.3.3.4.........3.4.4.4.........3.4.4.4.........3.3.4.4
------
...1.1.2.2.........1.1.1.2.........1.1.2.2.........1.2.2.2......
.....3.3.2.2.........1.1.1.4.........1.1.1.1.........4.4.4.4....
.......3.3.2.4.........4.4.4.4.........3.3.1.4.........3.3.4.4..
.........3.2.4.4.........3.3.4.4.........3.3.4.4.........3.4.4.4
CROSSREFS
Sequence in context: A336433 A099334 A281558 * A029812 A208562 A093120
KEYWORD
nonn
AUTHOR
R. H. Hardin Sep 17 2009
STATUS
approved